diff --git a/.gitignore b/.gitignore
index b23925f..a0aa52d 100644
--- a/.gitignore
+++ b/.gitignore
@@ -114,6 +114,10 @@ ENV/
 env.bak/
 venv.bak/
 
+# IntelliJ files
+/.idea
+/*.iml
+
 # Spyder project settings
 .spyderproject
 .spyproject
@@ -142,8 +146,9 @@ cython_debug/
 .DS_Store
 .vscode
 output/
-wa.db
-msgstore.db
+**/wa.db
+**/msgstore.db
 TODO.md
 test_locally.py
-tests/unit/tmp/*
\ No newline at end of file
+tests/unit/tmp/*
+/whatsapp_backup
\ No newline at end of file
diff --git a/main.py b/main.py
index 4a53e47..4c417e9 100644
--- a/main.py
+++ b/main.py
@@ -15,6 +15,9 @@
     chats_to_txt_raw,
 )
 
+CALL_LOGS_DIR = "/call_logs"
+CHAT_DIR = "/chats"
+
 
 def create_db_connection(file_path: str) -> Tuple[sqlite3.Connection, sqlite3.Cursor]:
     """Create a database connection and return it.
@@ -80,7 +83,7 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
         "--backup_specific_or_all_chat_call",
         "-e",
         nargs="*",
-        default="all",
+        default=["all"],
         help="Phone numbers (format: XXXXXXXXXXXX) of the chats and/or call logs that you want to extract from the database",
     )
     args = ap.parse_args()
@@ -95,20 +98,20 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
     )
 
     if args.backup_output_style == "raw_txt":
-        if args.backup_specific_or_all_chat_call == "all":
+        if args.backup_specific_or_all_chat_call == ["all"]:
             if "chats" in args.backup_strategy:
-                output_chat_directory = args.parsed_backup_output_dir + "/chats"
+                output_chat_directory = args.parsed_backup_output_dir + CHAT_DIR
                 if not os.path.exists(output_chat_directory):
                     os.makedirs(output_chat_directory)
                 chats = chat_builder.build_all_chats(msgdb_cursor, wadb_cursor)
                 for chat in tqdm(chats):
                     chats_to_txt_raw(
                         chat=chat,
-                        dir=output_chat_directory,
+                        folder=output_chat_directory,
                     )
             if "call_logs" in args.backup_strategy:
                 output_call_logs_directory = (
-                    args.parsed_backup_output_dir + "/call_logs"
+                        args.parsed_backup_output_dir + CALL_LOGS_DIR
                 )
                 if not os.path.exists(output_call_logs_directory):
                     os.makedirs(output_call_logs_directory)
@@ -118,12 +121,12 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
                 for call_log in tqdm(call_logs):
                     if call_log.calls:
                         call_logs_to_txt_raw(
-                            call_log=call_log, dir=output_call_logs_directory
+                            call_log=call_log, folder=output_call_logs_directory
                         )
         else:
             for ph_no in tqdm(args.backup_specific_or_all_chat_call):
                 if "chats" in args.backup_strategy:
-                    output_chat_directory = args.parsed_backup_output_dir + "/chats"
+                    output_chat_directory = args.parsed_backup_output_dir + CHAT_DIR
                     if not os.path.exists(output_chat_directory):
                         os.makedirs(output_chat_directory)
                     chat = chat_builder.build_chat_for_given_id_or_phone_number(
@@ -131,11 +134,11 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
                     )
                     chats_to_txt_raw(
                         chat=chat,
-                        dir=output_chat_directory,
+                        folder=output_chat_directory,
                     )
                 if "call_logs" in args.backup_strategy:
                     output_call_logs_directory = (
-                        args.parsed_backup_output_dir + "/call_logs"
+                            args.parsed_backup_output_dir + CALL_LOGS_DIR
                     )
                     if not os.path.exists(output_call_logs_directory):
                         os.makedirs(output_call_logs_directory)
@@ -146,24 +149,24 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
                     )
                     if call_log.calls:
                         call_logs_to_txt_raw(
-                            call_log=call_log, dir=output_call_logs_directory
+                            call_log=call_log, folder=output_call_logs_directory
                         )
 
     elif args.backup_output_style == "formatted_txt":
-        if args.backup_specific_or_all_chat_call == "all":
+        if args.backup_specific_or_all_chat_call == ["all"]:
             if "chats" in args.backup_strategy:
-                output_chat_directory = args.parsed_backup_output_dir + "/chats"
+                output_chat_directory = args.parsed_backup_output_dir + CHAT_DIR
                 if not os.path.exists(output_chat_directory):
                     os.makedirs(output_chat_directory)
                 chats = chat_builder.build_all_chats(msgdb_cursor, wadb_cursor)
                 for chat in tqdm(chats):
                     chats_to_txt_formatted(
                         chat=chat,
-                        dir=output_chat_directory,
+                        folder=output_chat_directory,
                     )
             if "call_logs" in args.backup_strategy:
                 output_call_logs_directory = (
-                    args.parsed_backup_output_dir + "/call_logs"
+                        args.parsed_backup_output_dir + CALL_LOGS_DIR
                 )
                 if not os.path.exists(output_call_logs_directory):
                     os.makedirs(output_call_logs_directory)
@@ -173,12 +176,12 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
                 for call_log in tqdm(call_logs):
                     if call_log.calls:
                         call_logs_to_txt_formatted(
-                            call_log=call_log, dir=output_call_logs_directory
+                            call_log=call_log, folder=output_call_logs_directory
                         )
         else:
             for ph_no in tqdm(args.backup_specific_or_all_chat_call):
                 if "chats" in args.backup_strategy:
-                    output_chat_directory = args.parsed_backup_output_dir + "/chats"
+                    output_chat_directory = args.parsed_backup_output_dir + CHAT_DIR
                     if not os.path.exists(output_chat_directory):
                         os.makedirs(output_chat_directory)
                     chat = chat_builder.build_chat_for_given_id_or_phone_number(
@@ -186,11 +189,11 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
                     )
                     chats_to_txt_formatted(
                         chat=chat,
-                        dir=output_chat_directory,
+                        folder=output_chat_directory,
                     )
                 if "call_logs" in args.backup_strategy:
                     output_call_logs_directory = (
-                        args.parsed_backup_output_dir + "/call_logs"
+                            args.parsed_backup_output_dir + CALL_LOGS_DIR
                     )
                     if not os.path.exists(output_call_logs_directory):
                         os.makedirs(output_call_logs_directory)
@@ -201,24 +204,24 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
                     )
                     if call_log.calls:
                         call_logs_to_txt_formatted(
-                            call_log=call_log, dir=output_call_logs_directory
+                            call_log=call_log, folder=output_call_logs_directory
                         )
 
     elif args.backup_output_style == "json":
-        if args.backup_specific_or_all_chat_call == "all":
+        if args.backup_specific_or_all_chat_call == ["all"]:
             if "chats" in args.backup_strategy:
-                output_chat_directory = args.parsed_backup_output_dir + "/chats"
+                output_chat_directory = args.parsed_backup_output_dir + CHAT_DIR
                 if not os.path.exists(output_chat_directory):
                     os.makedirs(output_chat_directory)
                 chats = chat_builder.build_all_chats(msgdb_cursor, wadb_cursor)
                 for chat in tqdm(chats):
                     chats_to_json(
                         chat=chat,
-                        dir=output_chat_directory,
+                        folder=output_chat_directory,
                     )
             if "call_logs" in args.backup_strategy:
                 output_call_logs_directory = (
-                    args.parsed_backup_output_dir + "/call_logs"
+                        args.parsed_backup_output_dir + CALL_LOGS_DIR
                 )
                 if not os.path.exists(output_call_logs_directory):
                     os.makedirs(output_call_logs_directory)
@@ -228,12 +231,12 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
                 for call_log in tqdm(call_logs):
                     if call_log.calls:
                         call_logs_to_json(
-                            call_log=call_log, dir=output_call_logs_directory
+                            call_log=call_log, folder=output_call_logs_directory
                         )
         else:
             for ph_no in tqdm(args.backup_specific_or_all_chat_call):
                 if "chats" in args.backup_strategy:
-                    output_chat_directory = args.parsed_backup_output_dir + "/chats"
+                    output_chat_directory = args.parsed_backup_output_dir + CHAT_DIR
                     if not os.path.exists(output_chat_directory):
                         os.makedirs(output_chat_directory)
                     chat = chat_builder.build_chat_for_given_id_or_phone_number(
@@ -241,11 +244,11 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
                     )
                     chats_to_json(
                         chat=chat,
-                        dir=output_chat_directory,
+                        folder=output_chat_directory,
                     )
                 if "call_logs" in args.backup_strategy:
                     output_call_logs_directory = (
-                        args.parsed_backup_output_dir + "/call_logs"
+                            args.parsed_backup_output_dir + CALL_LOGS_DIR
                     )
                     if not os.path.exists(output_call_logs_directory):
                         os.makedirs(output_call_logs_directory)
@@ -256,11 +259,11 @@ def close_db_connections(databases: List[sqlite3.Connection]) -> None:
                     )
                     if call_log.calls:
                         call_logs_to_json(
-                            call_log=call_log, dir=output_call_logs_directory
+                            call_log=call_log, folder=output_call_logs_directory
                         )
 
     else:
         close_db_connections([msgdb, wadb])
-        raise Exception("Invalid 'chat formatting' requested")
+        raise AssertionError("Invalid 'chat formatting' requested")
 
     close_db_connections([msgdb, wadb])
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..e213a65
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1,2 @@
+tqdm
+attrs
\ No newline at end of file
diff --git a/src/call_log_extractor/builder.py b/src/call_log_extractor/builder.py
index 2f7d9c4..eb82b5c 100644
--- a/src/call_log_extractor/builder.py
+++ b/src/call_log_extractor/builder.py
@@ -24,7 +24,7 @@ def build_call_for_given_id(
     if call_details:
         return Call(**call_details)
     else:
-        None
+        return None
 
 
 def build_call_log_for_given_id_or_phone_number(
@@ -53,7 +53,7 @@ def build_call_log_for_given_id_or_phone_number(
             msgdb_cursor=msgdb_cursor, phone_number=phone_number
         )
     else:
-        raise Exception("'jid_row_id' and 'phone_number' both cannot be None")
+        raise AssertionError("'jid_row_id' and 'phone_number' cannot both be None")
 
     dm_or_group = contact_resolver(
         wadb_cursor=wadb_cursor, raw_string_jid=raw_string_jid
@@ -61,10 +61,8 @@ def build_call_log_for_given_id_or_phone_number(
     call_log["caller_id"] = Contact(raw_string_jid=raw_string_jid, **dm_or_group)
 
     query = f"""SELECT call_log._id FROM 'call_log' WHERE call_log.jid_row_id={call_log.get("jid_row_id")}"""
-    exec = msgdb_cursor.execute(query)
-    res_query = list(chain.from_iterable(exec.fetchall()))
-    if res_query is None:
-        return None
+    execution = msgdb_cursor.execute(query)
+    res_query = list(chain.from_iterable(execution.fetchall()))
     call_log["calls"] = [
         build_call_for_given_id(msgdb_cursor, call_row_id)
         for call_row_id in sorted(res_query)
@@ -86,10 +84,8 @@ def build_all_call_logs(
         A generator of CallLog objects
     """
     query = "SELECT jid._id FROM 'jid'"
-    exec = msgdb_cursor.execute(query)
-    res_query = list(chain.from_iterable(exec.fetchall()))
-    if res_query is None:
-        return None
+    execution = msgdb_cursor.execute(query)
+    res_query = list(chain.from_iterable(execution.fetchall()))
 
     return (
         build_call_log_for_given_id_or_phone_number(
diff --git a/src/call_log_extractor/resolver.py b/src/call_log_extractor/resolver.py
index ec82244..05470b9 100644
--- a/src/call_log_extractor/resolver.py
+++ b/src/call_log_extractor/resolver.py
@@ -2,7 +2,7 @@
 from typing import Any, Dict, Tuple, Union
 
 
-def call_resolver(msgdb_cursor: sqlite3.Cursor, call_row_id: int) -> Dict[str, Any]:
+def call_resolver(msgdb_cursor: sqlite3.Cursor, call_row_id: int) -> Dict[str, Any] | None:
     """Fetch call data for a given call_row_id from the msgdb.
 
     Args:
@@ -16,11 +16,11 @@ def call_resolver(msgdb_cursor: sqlite3.Cursor, call_row_id: int) -> Dict[str, A
     SELECT call_log._id as call_row_id, call_log.from_me, call_log.timestamp, call_log.video_call, call_log.duration, call_log.call_result
     FROM 'call_log'
     WHERE call_log._id={call_row_id}"""
-    exec = msgdb_cursor.execute(msgdb_query)
-    res_query = exec.fetchone()
+    execution = msgdb_cursor.execute(msgdb_query)
+    res_query = execution.fetchone()
     if res_query is None:
         return None
-    res = dict(zip([col[0] for col in exec.description], res_query))
+    res = dict(zip([col[0] for col in execution.description], res_query))
     return res
 
 
@@ -51,15 +51,15 @@ def call_jid_resolver(
         FROM 'jid'
         WHERE jid.raw_string LIKE '%{phone_number}@%'"""
     else:
-        raise Exception("'jid_row_id' and 'phone_number' both cannot be None")
+        raise AssertionError("'jid_row_id' and 'phone_number' both cannot be None")
 
-    exec = msgdb_cursor.execute(msgdb_query)
-    res_query = exec.fetchone()
+    execution = msgdb_cursor.execute(msgdb_query)
+    res_query = execution.fetchone()
     if res_query is None:
         res_query = [
             None,
             None,
         ]  # Need some better logic to resolve when we don't have a contact in msgdb.db
-    res = dict(zip([col[0] for col in exec.description], res_query))
+    res = dict(zip([col[0] for col in execution.description], res_query))
     raw_string_jid = res.pop("raw_string_jid")
     return res, raw_string_jid
diff --git a/src/chat_extractor/builder.py b/src/chat_extractor/builder.py
index e1a4efb..53325d2 100644
--- a/src/chat_extractor/builder.py
+++ b/src/chat_extractor/builder.py
@@ -84,7 +84,7 @@ def build_chat_for_given_id_or_phone_number(
             msgdb_cursor=msgdb_cursor, phone_number=phone_number
         )
     else:
-        raise Exception("'chat_row_id' and 'phone_number' both cannot be None")
+        raise AssertionError("'chat_row_id' and 'phone_number' both cannot be None")
 
     dm_or_group = contact_resolver(
         wadb_cursor=wadb_cursor, raw_string_jid=raw_string_jid
@@ -97,10 +97,8 @@ def build_chat_for_given_id_or_phone_number(
         )
 
     query = f"""SELECT message._id FROM 'message' WHERE message.chat_row_id={chat.get("chat_id")}"""
-    exec = msgdb_cursor.execute(query)
-    res_query = list(chain.from_iterable(exec.fetchall()))
-    if res_query is None:
-        return None
+    execution = msgdb_cursor.execute(query)
+    res_query = list(chain.from_iterable(execution.fetchall()))
     chat["messages"] = [
         build_message_for_given_id(msgdb_cursor, wadb_cursor, message_id)
         for message_id in res_query
@@ -125,10 +123,8 @@ def build_all_chats(
         A generator of Chat objects.
     """
     query = "SELECT chat._id FROM 'chat'"
-    exec = msgdb_cursor.execute(query)
-    res_query = list(chain.from_iterable(exec.fetchall()))
-    if res_query is None:
-        return None
+    execution = msgdb_cursor.execute(query)
+    res_query = list(chain.from_iterable(execution.fetchall()))
 
     return (
         build_chat_for_given_id_or_phone_number(
diff --git a/src/chat_extractor/resolver.py b/src/chat_extractor/resolver.py
index 885be43..e713598 100644
--- a/src/chat_extractor/resolver.py
+++ b/src/chat_extractor/resolver.py
@@ -2,7 +2,7 @@
 from typing import Any, Dict, Tuple, Union
 
 
-def media_resolver(msgdb_cursor: sqlite3.Cursor, message_row_id: int) -> Dict[str, Any]:
+def media_resolver(msgdb_cursor: sqlite3.Cursor, message_row_id: int) -> Dict[str, Any] | None:
     """Fetch media related data for a given message_id from the msgdb.
 
     Args:
@@ -13,17 +13,17 @@ def media_resolver(msgdb_cursor: sqlite3.Cursor, message_row_id: int) -> Dict[st
         Dict[str, Any]: Dictionary containing 'message_id', 'media_job_uuid', 'file_path' and 'mime_type' keys.
     """
     query = f"SELECT message_media.message_row_id as message_id, message_media.media_job_uuid, message_media.file_path, message_media.mime_type FROM message_media WHERE message_media.message_row_id='{message_row_id}'"
-    exec = msgdb_cursor.execute(query)
-    res_query = exec.fetchone()
+    execution = msgdb_cursor.execute(query)
+    res_query = execution.fetchone()
     if res_query is None:
         return None
-    res = dict(zip([col[0] for col in exec.description], res_query))
+    res = dict(zip([col[0] for col in execution.description], res_query))
     return res
 
 
 def geo_position_resolver(
     msgdb_cursor: sqlite3.Cursor, message_row_id: int
-) -> Dict[str, Any]:
+) -> Dict[str, Any] | None:
     """Fetch geo-position related data for a given message_id from the msgdb.
 
     Args:
@@ -34,11 +34,11 @@ def geo_position_resolver(
         Dict[str, Any]: Dictionary containing 'message_id', 'latitude' and 'longitude' keys.
     """
     query = f"SELECT message_location.message_row_id as message_id, message_location.latitude, message_location.longitude FROM message_location WHERE message_location.message_row_id='{message_row_id}'"
-    exec = msgdb_cursor.execute(query)
-    res_query = exec.fetchone()
+    execution = msgdb_cursor.execute(query)
+    res_query = execution.fetchone()
     if res_query is None:
         return None
-    res = dict(zip([col[0] for col in exec.description], res_query))
+    res = dict(zip([col[0] for col in execution.description], res_query))
     return res
 
 
@@ -63,14 +63,14 @@ def message_resolver(
     WHERE message._id={message_row_id}
     """
 
-    exec = msgdb_cursor.execute(query)
-    res_query = exec.fetchone()
+    execution = msgdb_cursor.execute(query)
+    res_query = execution.fetchone()
     if res_query is None:
         res_query = [
             None,
             None,
         ]
-    res = dict(zip([col[0] for col in exec.description], res_query))
+    res = dict(zip([col[0] for col in execution.description], res_query))
     raw_string_jid = res.pop("raw_string_jid")
     return res, raw_string_jid
 
@@ -104,15 +104,15 @@ def chat_resolver(
         JOIN 'jid' ON chat.jid_row_id=jid._id
         WHERE jid.raw_string LIKE '%{phone_number}@%'"""
     else:
-        raise Exception("'chat_row_id' and 'phone_number' both cannot be None")
+        raise AssertionError("'chat_row_id' and 'phone_number' both cannot be None")
 
-    exec = msgdb_cursor.execute(msgdb_query)
-    res_query = exec.fetchone()
+    execution = msgdb_cursor.execute(msgdb_query)
+    res_query = execution.fetchone()
     if res_query is None:
         res_query = [
             None,
             None,
         ]  # Need some better logic to resolve when we don't have a contact in msgdb.db
-    res = dict(zip([col[0] for col in exec.description], res_query))
+    res = dict(zip([col[0] for col in execution.description], res_query))
     raw_string_jid = res.pop("raw_string_jid")
     return res, raw_string_jid
diff --git a/src/common.py b/src/common.py
index 613ba9f..565d76f 100644
--- a/src/common.py
+++ b/src/common.py
@@ -17,14 +17,14 @@ def contact_resolver(
     query = f"""
     SELECT wa_contacts.display_name as name, wa_contacts.number FROM 'wa_contacts' WHERE wa_contacts.jid="{raw_string_jid}"
     """
-    exec = wadb_cursor.execute(query)
-    res_query = exec.fetchone()
+    execution = wadb_cursor.execute(query)
+    res_query = execution.fetchone()
     if res_query is None:
         res_query = [
             None,
             None,
         ]  # Need some better logic to resolve when we don't have a contact in wa.db
-    res = dict(zip([col[0] for col in exec.description], res_query))
+    res = dict(zip([col[0] for col in execution.description], res_query))
     if res.get("name"):
         if "/" in res["name"]:
             res["name"] = res.get("name").replace("/", "_")
diff --git a/src/exports/to_json.py b/src/exports/to_json.py
index bd79cea..1d739a0 100644
--- a/src/exports/to_json.py
+++ b/src/exports/to_json.py
@@ -5,7 +5,7 @@
 from ..models import CallLog, Chat, Contact, GroupName
 
 
-def chats_to_json(chat: Chat, dir: str) -> None:
+def chats_to_json(chat: Chat, folder: str) -> None:
     """Store chat as a JSON file.
 
     It takes a chat object and a directory, and writes a json file to the directory with the chat's
@@ -13,7 +13,7 @@ def chats_to_json(chat: Chat, dir: str) -> None:
 
     Args:
         chat (Chat): Chat - the chat object to be converted to JSON
-        dir (str): The directory to save the chats to.
+        folder (str): The directory to save the chats to.
 
     Returns:
         None: Creates .json file of the chat in the given directory
@@ -28,11 +28,11 @@ def chats_to_json(chat: Chat, dir: str) -> None:
     else:
         chat_title_details = ""
 
-    with open(f"{dir}/{chat_title_details}.json", "w", encoding="utf8") as file:
+    with open(f"{folder}/{chat_title_details}.json", "w", encoding="utf8") as file:
         json.dump(asdict(chat), file, sort_keys=True, indent=4, ensure_ascii=False)
 
 
-def call_logs_to_json(call_log: CallLog, dir: str) -> None:
+def call_logs_to_json(call_log: CallLog, folder: str) -> None:
     """Store call logs as a JSON file.
 
     It takes a `CallLog` object and a directory path, and writes a JSON file to the directory with the
@@ -40,7 +40,7 @@ def call_logs_to_json(call_log: CallLog, dir: str) -> None:
 
     Args:
         call_log (CallLog): CallLog - The call log object to be converted to JSON.
-        dir (str): The directory where the JSON files will be saved.
+        folder (str): The directory where the JSON files will be saved.
 
     Returns:
         None: Creates .json file of the chat in the given directory
@@ -50,5 +50,5 @@ def call_logs_to_json(call_log: CallLog, dir: str) -> None:
     else:
         caller_id_details = f"+{call_log.caller_id.raw_string_jid.split('@')[0]}"
 
-    with open(f"{dir}/{caller_id_details}.json", "w", encoding="utf8") as file:
+    with open(f"{folder}/{caller_id_details}.json", "w", encoding="utf8") as file:
         json.dump(asdict(call_log), file, sort_keys=True, indent=4, ensure_ascii=False)
diff --git a/src/exports/to_txt.py b/src/exports/to_txt.py
index 74c405a..4121ad3 100644
--- a/src/exports/to_txt.py
+++ b/src/exports/to_txt.py
@@ -4,12 +4,12 @@
 from ..models import CallLog, Chat, Contact, GroupName, Message
 
 
-def chats_to_txt_raw(chat: Chat, dir: str) -> None:
+def chats_to_txt_raw(chat: Chat, folder: str) -> None:
     """Store chat messages in a text file without formatting.
 
     Args:
         chat (Chat): Chat to be formatted.
-        dir (str): Directory to write the formatted chat.
+        folder (str): Directory to write the formatted chat.
 
     Returns:
         None: Creates .txt file of the chat in the given directory
@@ -26,40 +26,40 @@ def chats_to_txt_raw(chat: Chat, dir: str) -> None:
         chat_title_details = ""
 
     messages = "\n".join([str(message) for message in chat.messages])
-    with open(f"{dir}/{chat_title_details}-raw.txt", "w", encoding="utf-8") as file:
+    with open(f"{folder}/{chat_title_details}-raw.txt", "w", encoding="utf-8") as file:
         file.write(f"{chat_title_details}\n\n{messages}")
 
 
-def chats_to_txt_formatted(chat: Chat, dir: str) -> None:
+def chats_to_txt_formatted(chat: Chat, folder: str) -> None:
     """Format chat messages in a readable format and store them as a text file.
 
     Args:
         chat (Chat): Chat to be formatted.
-        dir (str): Directory to write the formatted chat.
+        folder (str): Directory to write the formatted chat.
 
     Returns:
         None: Creates .txt file of the chat in the given directory
     """
     message_list = []
 
-    def resolve_sender_name(message: Message) -> str:
+    def resolve_sender_name(msg: Message) -> str:
         """Utility function to extract 'sender_name' from a given message.
 
         Args:
-            message (Message): Message from which we want to extract sender_name.
+            msg (Message): Message from which we want to extract sender_name.
 
         Returns:
             str: sender_name
         """
-        if message.from_me:
+        if msg.from_me:
             sender_name = "Me"
         else:
             sender_name = (
-                message.sender_contact.name
-                if message.sender_contact.name is not None
-                else message.sender_contact.raw_string_jid[
-                    : message.sender_contact.raw_string_jid.index("@")
-                ]
+                msg.sender_contact.name
+                if msg.sender_contact.name is not None
+                else msg.sender_contact.raw_string_jid[
+                     : msg.sender_contact.raw_string_jid.index("@")
+                     ]
             )
         return sender_name
 
@@ -90,7 +90,7 @@ def find_reply(
             # If there is no data or media or reply_to, we can assume that the message was about change in chat settings.
             message_str = f"[{date_time}] 'Change in the chat settings'"
         else:
-            sender_name = resolve_sender_name(message=message)
+            sender_name = resolve_sender_name(msg=message)
 
             message_str = (
                 f"[{date_time}]: {sender_name} - {message.text_data}"
@@ -102,7 +102,7 @@ def find_reply(
             if message.reply_to:
                 orig_message = next(
                     find_reply(
-                        lambda x: message.reply_to == x.key_id,
+                        lambda x, msg=message: msg.reply_to == x.key_id,
                         chat.messages[:idx],
                     ),
                     None,
@@ -146,16 +146,16 @@ def find_reply(
         chat_title_details = ""
 
     messages = "\n".join(message_list)
-    with open(f"{dir}/{chat_title_details}.txt", "w", encoding="utf-8") as file:
+    with open(f"{folder}/{chat_title_details}.txt", "w", encoding="utf-8") as file:
         file.write(f"{chat_title_details}\n\n{messages}")
 
 
-def call_logs_to_txt_raw(call_log: CallLog, dir: str) -> None:
+def call_logs_to_txt_raw(call_log: CallLog, folder: str) -> None:
     """Store call logs in a text file without formatting.
 
     Args:
         call_log (CallLog): CallLog to be formatted.
-        dir (str): Directory to write the formatted call log.
+        folder (str): Directory to write the formatted call log.
 
     Returns:
         None: Creates .txt file of the call log in the given directory.
@@ -166,16 +166,16 @@ def call_logs_to_txt_raw(call_log: CallLog, dir: str) -> None:
         caller_id_details = f"+{call_log.caller_id.raw_string_jid.split('@')[0]}"
 
     call_logs = "\n".join([str(call) for call in call_log.calls])
-    with open(f"{dir}/{caller_id_details}-raw.txt", "w", encoding="utf-8") as file:
+    with open(f"{folder}/{caller_id_details}-raw.txt", "w", encoding="utf-8") as file:
         file.write(f"{caller_id_details}\n\n{call_logs}")
 
 
-def call_logs_to_txt_formatted(call_log: CallLog, dir: str) -> None:
+def call_logs_to_txt_formatted(call_log: CallLog, folder: str) -> None:
     """Format call logs in a readable format and store them as a text file.
 
     Args:
         call_log (CallLog): CallLog to be formatted.
-        dir (str): Directory to write the formatted call log.
+        folder (str): Directory to write the formatted call log.
 
     Returns:
         None: Creates .txt file of the call log in the given directory.
@@ -229,5 +229,5 @@ def seconds_to_hms(duration_in_sec: int) -> str:
             call_log_list.append(call_log_str)
 
     call_logs = "\n".join(call_log_list)
-    with open(f"{dir}/{caller_id_details}.txt", "w", encoding="utf-8") as file:
+    with open(f"{folder}/{caller_id_details}.txt", "w", encoding="utf-8") as file:
         file.write(f"{caller_id_details}\n\n{call_logs}")
diff --git a/src/models.py b/src/models.py
index cb1e130..b0467d9 100644
--- a/src/models.py
+++ b/src/models.py
@@ -1,4 +1,3 @@
-from datetime import datetime
 from typing import List, Optional, Union
 
 from attrs import define
@@ -45,21 +44,21 @@ class GeoPosition(object):
 class Message(object):
     message_id: int  # Message ID. Resolved from `message._id`.
     key_id: str  # Key ID. Resolved from `message.key_id`.
-    chat_id: str  # Which chat does this message belong to. Resolved from `message.chat_row_id`.
+    chat_id: int  # Which chat does this message belong to. Resolved from `message.chat_row_id`.
     from_me: int  # Whether this message is sent by me or not. Resolved from `message.from_me -> bool`.
     sender_contact: Optional[Contact]
-    timestamp: datetime  # When was this message sent. Resolved from `message.received_timestamp`.
+    timestamp: int  # When was this message sent. Resolved from `message.received_timestamp`.
     text_data: Optional[
         str
     ]  # The actual text message. Resolved from `message.text_data`.
     media: Optional[Media]
     geo_position: Optional[GeoPosition]
-    reply_to: str  # If a reply, it is a reply to which message. Resolved from `message._id -> message_quoted.message_row_id -> message_quoted.key_id`
+    reply_to: str| None  # If a reply, it is a reply to which message. Resolved from `message._id -> message_quoted.message_row_id -> message_quoted.key_id`
 
 
 @define
 class Chat(object):
-    chat_id: str  # Chat ID. Resolved from `chat._id`.
+    chat_id: int  # Chat ID. Resolved from `chat._id`.
     chat_title: Optional[Union[Contact, GroupName]]  # Chat title.
     messages: List[Optional[Message]]
 
@@ -68,7 +67,7 @@ class Chat(object):
 class Call(object):
     call_row_id: int  # Call row ID. Resolved from `call_log._id`.
     from_me: int  # Whether this call was made by me or not. Resolved from `call_log.from_me -> bool`.
-    timestamp: datetime  # When was this call made. Resolved from `call_log.timestamp`.
+    timestamp: int  # When was this call made. Resolved from `call_log.timestamp`.
     video_call: int  # Whether this call was a video call or not. Resolved from `call_log.video_call -> bool`.
     duration: int  # Duration of the call. Resolved from `call_log.duration`.
     call_result: int
diff --git a/tests/unit/test_call_log_resolver.py b/tests/unit/test_call_log_resolver.py
index a1668eb..4d8d829 100644
--- a/tests/unit/test_call_log_resolver.py
+++ b/tests/unit/test_call_log_resolver.py
@@ -71,7 +71,7 @@ def test_call_jid_resolver_with_phone_number():
     msgdb = sqlite3.connect("tests/unit/data/test_msgstore.db")
     msgdb_cursor = msgdb.cursor()
 
-    phone_numbers = [979017585714, 899167416177, 885402477365]
+    phone_numbers = ["979017585714", "899167416177", "885402477365"]
     for phone_number, expected_result in zip(phone_numbers, expected_results):
         assert (
             resolver.call_jid_resolver(msgdb_cursor, phone_number=phone_number)
diff --git a/tests/unit/test_exports_to_json.py b/tests/unit/test_exports_to_json.py
index 7c9b56c..3a5bbd1 100644
--- a/tests/unit/test_exports_to_json.py
+++ b/tests/unit/test_exports_to_json.py
@@ -75,7 +75,7 @@ def test_export_chats_to_json(tmp_path):
 
     test_chat_dir = tmp_path / "chats"
     test_chat_dir.mkdir()
-    to_json.chats_to_json(chat=test_chat, dir=f"{test_chat_dir}")
+    to_json.chats_to_json(chat=test_chat, folder=f"{test_chat_dir}")
 
     with open(
         f"{test_chat_dir}/+{test_chat.chat_title.raw_string_jid.split('@')[0]}.json",
@@ -126,7 +126,7 @@ def test_export_call_logs_to_json(tmp_path):
 
     test_call_log_dir = tmp_path / "call_logs"
     test_call_log_dir.mkdir()
-    to_json.call_logs_to_json(call_log=test_call_log, dir=f"{test_call_log_dir}")
+    to_json.call_logs_to_json(call_log=test_call_log, folder=f"{test_call_log_dir}")
 
     with open(
         f"{test_call_log_dir}/{test_call_log.caller_id.name} ({test_call_log.caller_id.number}).json",
diff --git a/tests/unit/test_exports_to_txt.py b/tests/unit/test_exports_to_txt.py
index 988b152..7fcd811 100644
--- a/tests/unit/test_exports_to_txt.py
+++ b/tests/unit/test_exports_to_txt.py
@@ -88,7 +88,7 @@ def test_export_chats_to_txt_raw(tmp_path):
     test_chat_dir = tmp_path / "chats"
     test_chat_dir.mkdir()
 
-    to_txt.chats_to_txt_raw(chat=test_chat, dir=f"{test_chat_dir}")
+    to_txt.chats_to_txt_raw(chat=test_chat, folder=f"{test_chat_dir}")
     with open(
         f"{test_chat_dir}/{test_chat.chat_title.name} ({test_chat.chat_title.number})-raw.txt"
     ) as f:
@@ -162,7 +162,7 @@ def test_export_chats_to_txt_formatted(tmp_path):
 
     test_chat_dir = tmp_path / "chats"
     test_chat_dir.mkdir()
-    to_txt.chats_to_txt_formatted(chat=test_chat, dir=f"{test_chat_dir}")
+    to_txt.chats_to_txt_formatted(chat=test_chat, folder=f"{test_chat_dir}")
     with open(f"{test_chat_dir}/{test_chat.chat_title.name}.txt") as f:
         assert f.read() == expected_export_chats_to_txt_formatted_result
 
@@ -198,7 +198,7 @@ def test_export_call_logs_to_txt_raw(tmp_path):
 
     test_call_log_dir = tmp_path / "call_logs"
     test_call_log_dir.mkdir()
-    to_txt.call_logs_to_txt_raw(call_log=test_call_log, dir=f"{test_call_log_dir}")
+    to_txt.call_logs_to_txt_raw(call_log=test_call_log, folder=f"{test_call_log_dir}")
     with open(
         f"{test_call_log_dir}/{test_call_log.caller_id.name} ({test_call_log.caller_id.number})-raw.txt"
     ) as f:
@@ -237,7 +237,7 @@ def test_export_call_logs_to_txt_formatted(tmp_path):
     test_call_log_dir = tmp_path / "call_logs"
     test_call_log_dir.mkdir()
     to_txt.call_logs_to_txt_formatted(
-        call_log=test_call_log, dir=f"{test_call_log_dir}"
+        call_log=test_call_log, folder=f"{test_call_log_dir}"
     )
     with open(
         f"{test_call_log_dir}/{test_call_log.caller_id.name} ({test_call_log.caller_id.number}).txt"