diff --git a/packages/google-cloud-texttospeech/testing/constraints-3.10.txt b/packages/google-cloud-texttospeech/testing/constraints-3.10.txt
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/packages/google-cloud-texttospeech/testing/constraints-3.11.txt b/packages/google-cloud-texttospeech/testing/constraints-3.11.txt
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/packages/google-cloud-texttospeech/testing/constraints-3.6.txt b/packages/google-cloud-texttospeech/testing/constraints-3.6.txt
new file mode 100644
index 000000000000..2923be131cf5
--- /dev/null
+++ b/packages/google-cloud-texttospeech/testing/constraints-3.6.txt
@@ -0,0 +1,10 @@
+# This constraints file is used to check that lower bounds
+# are correct in setup.py
+# List *all* library dependencies and extras in this file.
+# Pin the version to the lower bound.
+#
+# e.g., if setup.py has "foo >= 1.14.0, < 2.0.0dev",
+# Then this file should have foo==1.14.0
+google-api-core==1.22.0
+proto-plus==1.4.0
+libcst==0.2.5
\ No newline at end of file
diff --git a/packages/google-cloud-texttospeech/testing/constraints-3.7.txt b/packages/google-cloud-texttospeech/testing/constraints-3.7.txt
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/packages/google-cloud-texttospeech/testing/constraints-3.8.txt b/packages/google-cloud-texttospeech/testing/constraints-3.8.txt
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/packages/google-cloud-texttospeech/testing/constraints-3.9.txt b/packages/google-cloud-texttospeech/testing/constraints-3.9.txt
new file mode 100644
index 000000000000..e69de29bb2d1