Simplify metadata typing

twine/commands/check.py

@@ -80,16 +80,16 @@ def _check_file(
     package = package_file.PackageFile.from_filename(filename, comment=None)
 
     metadata = package.metadata_dictionary()
-    description = metadata["description"]
-    description_content_type = metadata["description_content_type"]
+    description = cast(str, metadata["description"])
+    description_content_type = cast(str, metadata["description_content_type"])
 
     if description_content_type is None:
         warnings.append(
             "`long_description_content_type` missing. defaulting to `text/x-rst`."
         )
         description_content_type = "text/x-rst"
 
-    content_type, params = cgi.parse_header(cast(str, description_content_type))
+    content_type, params = cgi.parse_header(description_content_type)
     renderer = _RENDERERS.get(content_type, _RENDERERS[None])
 
     if description in {None, "UNKNOWN\n\n\n"}:

twine/package.py

@@ -16,7 +16,6 @@
 import io
 import os
 import subprocess
-from typing import IO
 from typing import Dict
 from typing import Optional
 from typing import Sequence
@@ -46,7 +45,7 @@
     ".zip": "sdist",
 }
 
-MetadataValue = Union[str, Sequence[str], Tuple[str, IO, str]]
+MetadataValue = Union[str, Sequence[str]]
 
 
 class PackageFile:

twine/repository.py

@@ -103,9 +103,7 @@ def close(self) -> None:
         self.session.close()
 
     @staticmethod
-    def _convert_data_to_list_of_tuples(
-        data: Dict[str, package_file.MetadataValue]
-    ) -> List[Tuple[str, package_file.MetadataValue]]:
+    def _convert_data_to_list_of_tuples(data: Dict[str, Any]) -> List[Tuple[str, Any]]:
         data_to_send = []
         for key, value in data.items():
             if key in KEYWORDS_TO_NOT_FLATTEN or not isinstance(value, (list, tuple)):