Fix commons type hints

Author: bonjourmauko

openfisca_core/commons/imports.py

@@ -1,3 +1,6 @@
+from types import ModuleType
+from typing import Tuple
+
 import importlib
 import os
 import traceback
@@ -8,7 +11,7 @@
 from openfisca_core.warnings import LibYAMLWarning
 
 
-def import_country_package(country_package_name):
+def import_country_package(country_package_name: str) -> ModuleType:
     """Import a country package."""
 
     try:
@@ -27,7 +30,7 @@ def import_country_package(country_package_name):
         raise ImportError(message) from error
 
 
-def import_yaml():
+def import_yaml() -> Tuple[ModuleType, yaml.cyaml.CLoader]:
     """Import the yaml library."""
 
     try:

openfisca_core/indexed_enums/enum.py

@@ -21,7 +21,7 @@ def __init__(self, name: str) -> None:
         # When the enum item is initialized, self._member_names_ contains the
         # names of the previously initialized items, so its length is the index
         # of this item.
-        self.index = len(self._member_names_)
+        self.index = len(self._member_names_)  # type: ignore
 
     # Bypass the slow Enum.__eq__
     __eq__ = object.__eq__

openfisca_core/tracers/trace_node.py

@@ -8,7 +8,6 @@
     import numpy
 
     from openfisca_core.indexed_enums import EnumArray
-    from openfisca_core.periods import Period
 
     Array = typing.Union[EnumArray, numpy.typing.ArrayLike]
     Time = typing.Union[float, int]