diff --git a/pytransifex/api.py b/pytransifex/api.py
index 11546a2..eb29918 100644
--- a/pytransifex/api.py
+++ b/pytransifex/api.py
@@ -237,16 +237,30 @@ def get_translation(
             )
 
     @ensure_login
-    def list_languages(self, project_slug: str, resource_slug: str) -> list[Any]:
+    def list_languages(self, project_slug: str, resource_slug: str) -> list[str]:
         """
         List languages for which there exist translations under the given resource.
         """
         if self.projects:
             if project := self.projects.get(slug=project_slug):
                 if resource := project.fetch("resources").get(slug=resource_slug):
-                    logging.info(f"Obtained these languages")
-                    # FIXME: Extract a list[str] mapping to resource languages
-                    return resource
+                    it = tx_api.ResourceLanguageStats.filter(
+                        project=project, resource=resource
+                    ).all()
+
+                    language_codes = []
+                    for tr in it:
+                        """
+                        FIXME
+                        This is hideous and probably unsound for some language_codes.
+                        Couldn't find a more direct accessor to language codes.
+                        """
+                        code = str(tr).rsplit("_", 1)[-1][:-1]
+                        language_codes.append(code)
+
+                    logging.info(f"Obtained these languages: {language_codes}")
+                    return language_codes
+
                 raise ValueError(
                     f"Unable to find any resource with this slug: '{resource_slug}'"
                 )
@@ -263,7 +277,7 @@ def create_language(
         *,
         project_slug: str,
         language_code: str,
-        coordinators: None | list[Any] = None,
+        coordinators: None | list[str] = None,
     ):
         """Create a new language resource in the remote Transifex repository"""
         if project := self.get_project(project_slug=project_slug):
diff --git a/tests/test_api.py b/tests/test_api.py
index fd23740..33f073d 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -107,7 +107,7 @@ def test8_get_translation(self):
 
     def test9_project_exists(self):
         verdict = self.tx.project_exists(project_slug=self.project_slug)
-        assert verdict is not None
+        assert verdict
 
     def test10_ping(self):
         self.tx.ping()
diff --git a/tests/test_cli.py b/tests/test_cli.py
index 0dc5d4b..c9dd45e 100644
--- a/tests/test_cli.py
+++ b/tests/test_cli.py
@@ -58,7 +58,7 @@ def test1_init(self):
         assert passed
 
     def test2_push(self):
-        result = self.runner.invoke(cli, ["push", "-in", str(self.path_to_file)])
+        result = self.runner.invoke(cli, ["push", "-in", str(self.path_to_input_dir)])
         passed = result.exit_code == 0
         logging.info(result.output)
         assert passed
diff --git a/tests/test_utils.py b/tests/test_utils.py
index b5d4b35..b9edcb5 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -26,3 +26,7 @@ def test1_map_async(self):
     def test2_map_async(self):
         res = concurrently(fn=fn, args=self.args)
         assert res == self.res
+
+
+if __name__ == "__main__":
+    unittest.main()