MAINT: Restore typing completeness

Fix typing issues
isort, black and flake8 compat

arch/univariate/base.py

@@ -11,7 +11,6 @@
 import pandas as pd
 from pandas import DataFrame, Series
 from pandas.util._decorators import deprecate_kwarg
-from arch.vendor import cached_property
 from scipy.optimize import OptimizeResult
 import scipy.stats as stats
 from statsmodels.iolib.summary import Summary, fmt_2cols, fmt_params
@@ -34,6 +33,7 @@
     starting_value_warning,
 )
 from arch.utility.testing import WaldTestStatistic
+from arch.vendor import cached_property
 
 try:
     from matplotlib.figure import Figure

arch/univariate/mean.py

@@ -7,7 +7,6 @@
 
 import numpy as np
 from pandas import DataFrame
-from arch.vendor import cached_property
 from scipy.optimize import OptimizeResult
 from statsmodels.tsa.tsatools import lagmat
 
@@ -40,6 +39,7 @@
     ensure1d,
     parse_dataframe,
 )
+from arch.vendor import cached_property
 
 __all__ = ["HARX", "ConstantMean", "ZeroMean", "ARX", "arch_model", "LS"]
 

arch/utility/array.py

@@ -9,9 +9,9 @@
 
 import numpy as np
 from pandas import DataFrame, DatetimeIndex, Index, NaT, Series, Timestamp, to_datetime
-from arch.vendor import cached_property
 
 from arch.typing import AnyPandas, ArrayLike, DateLike, NDArray
+from arch.vendor import cached_property
 
 __all__ = [
     "ensure1d",

arch/utility/testing.py

@@ -1,8 +1,9 @@
 from typing import Dict, Optional
 
-from arch.vendor import cached_property
 from scipy.stats import chi2
 
+from arch.vendor import cached_property
+
 __all__ = ["WaldTestStatistic"]
 
 

arch/vendor/property_cached.py

@@ -32,9 +32,9 @@
 
 import asyncio
 import functools
-import sys
 import threading
 from time import time
+from typing import Any, Mapping
 import weakref
 
 __author__ = "Martin Larralde"
@@ -52,21 +52,12 @@ class cached_property(property):
 
     _sentinel = object()
 
-    if sys.version_info[0] < 3:
-
-        def _update_wrapper(self, func):
-            self.__doc__ = getattr(func, "__doc__", None)
-            self.__module__ = getattr(func, "__module__", None)
-            self.__name__ = getattr(func, "__name__", None)
-
-    else:
-
-        _update_wrapper = functools.update_wrapper
+    _update_wrapper = functools.update_wrapper
 
     def __init__(self, func) -> None:
-        self.cache = weakref.WeakKeyDictionary()
+        self.cache: Mapping[str, Any] = weakref.WeakKeyDictionary()
         self.func = func
-        self._update_wrapper(func)
+        self._update_wrapper(func)  # type: ignore
 
     def __get__(self, obj, cls):
         if obj is None: