Run mypy during pre-commit

.pre-commit-config.yaml

@@ -30,3 +30,17 @@ repos:
         name: lint (code)
         types: [python]
         exclude: "^(docs/|examples/|setup.py$)"
+- repo: local
+  hooks:
+    - id: mypy
+      name: mypy
+      entry: "mypy --no-warn-unused-ignores jepler_udecimal"
+      language: python
+      additional_dependencies: ["mypy==0.910"]
+      types: [python]
+      # use require_serial so that script
+      # is only called once per commit
+      require_serial: true
+      # Print the number of files as a sanity-check
+      verbose: true
+      pass_filenames: false

jepler_udecimal/__init__.py

@@ -141,7 +141,7 @@ try:
 
     DecimalTuple = _namedtuple("DecimalTuple", "sign digits exponent")
 except ImportError:
-    DecimalTuple = lambda *args: args
+    DecimalTuple = lambda *args: args  # type: ignore
 
 # Rounding
 ROUND_DOWN = "ROUND_DOWN"
@@ -3574,7 +3574,7 @@ class Context(object):
             self._ignored_flags.remove(flag)
 
     # We inherit object.__hash__, so we must deny this explicitly
-    __hash__ = None
+    __hash__ = None  # type: ignore
 
     def Etiny(self):
         """Returns Etiny (= Emin - prec + 1)"""
@@ -5372,7 +5372,7 @@ ExtendedContext = Context(
 try:
     import re
 except:
-    import ure as re
+    import ure as re  # type: ignore
 
 _parser = re.compile(  # A numeric string consists of:
     r"([-+])?"  # an optional sign, followed by either...    # 1