Add main() to verify-hashes; remove unused import

scripts/verify-hashes

@@ -6,12 +6,6 @@ import sys
 from pathlib import Path
 import utils
 
-try:
-    import tomllib
-except ModuleNotFoundError:
-    # pre-Python 3.11 compatibility
-    import toml as tomllib
-
 # For a requirements file in one of our projects, this script checks if we have at
 # least one corresponding sha256sum (for the source tarball) for each dependency.
 # The script should be run from the project directory whose requirements you
@@ -21,11 +15,12 @@ except ModuleNotFoundError:
 # Once Poetry support is stable across all components, requirements.txt support
 # can be deprecated.
 
-""""
-Ensure that we have at least one signed SHA256 sum for each dependency declared
-in a project's requirements file. This will be the source tarball.
-"""
-if __name__ == "__main__":
+
+def main():
+    """ "
+    Ensure that we have at least one signed SHA256 sum for each dependency declared
+    in a project's requirements file. This will be the source tarball.
+    """
     if len(sys.argv) != 2:
         print("Usage: ./scripts/verify-hashes path/to/sha256sums.txt")
         sys.exit(1)
@@ -69,3 +64,7 @@ if __name__ == "__main__":
             sys.exit(1)
 
     sys.exit(0)
+
+
+if __name__ == "__main__":
+    main()