BUG: mypy: bump mypy version and fix new typing errors

`mypy` 0.770 was broken on Python 3.9.0a5. Hence, the requirement
file is altered to always download the latest `mypy` version.
See https://mail.python.org/pipermail/scipy-dev/2021-February/024580.html

Also, latest mypy version reported some more typing errors which have been
resolved in this commit.

mypy.ini

@@ -385,6 +385,9 @@ ignore_errors = True
 [mypy-scipy.spatial.tests.test_distance]
 ignore_errors = True
 
+[mypy-scipy.stats.tests.test_qmc]
+ignore_errors = True
+
 #
 # Files referencing compiled code that needs stubs added.
 #

mypy_requirements.txt

@@ -1,3 +1,3 @@
-mypy==0.770
+mypy
 typing_extensions
 git+git://github.com/numpy/numpy-stubs.git@master

scipy/fft/tests/test_backend.py

@@ -2,7 +2,7 @@
 import scipy.fft
 from scipy.fft import set_backend
 from scipy.fft import _pocketfft
-from scipy.fft.tests import mock_backend
+from scipy.fft.tests import mock_backend  # type: ignore[import]
 
 from numpy.testing import assert_allclose, assert_equal
 import pytest

scipy/odr/_add_newdocs.py

@@ -1,4 +1,4 @@
-from numpy import add_newdoc
+from numpy import add_newdoc  # type: ignore[attr-defined]
 
 add_newdoc('scipy.odr', 'odr',
     """

scipy/special/orthogonal.pyi

@@ -286,7 +286,7 @@ class orthopoly1d(numpy.poly1d):
     def limits(self) -> Tuple[float, float]: ...
     def wfunc(x: float) -> float: ...
     # TODO: ArrayLike
-    def __call__(self, x: Any) -> numpy.ndarray: ...
+    def __call__(self, x: Any) -> Any: ...
 
 def legendre(n: _IntegerType, monic: bool = ...) -> orthopoly1d: ...
 def chebyt(n: _IntegerType, monic: bool = ...) -> orthopoly1d: ...

scipy/stats/tests/test_stats.py

@@ -2831,12 +2831,13 @@ def test_percentileofscore():
     assert_raises(ValueError, pcos, [1, 2, 3, 3, 4], 3, kind='unrecognized')
 
 
-PowerDivCase = namedtuple('Case', ['f_obs', 'f_exp', 'ddof', 'axis',
-                                   'chi2',     # Pearson's
-                                   'log',      # G-test (log-likelihood)
-                                   'mod_log',  # Modified log-likelihood
-                                   'cr',       # Cressie-Read (lambda=2/3)
-                                   ])
+PowerDivCase = namedtuple('Case',  # type: ignore[name-match]
+                          ['f_obs', 'f_exp', 'ddof', 'axis',
+                           'chi2',     # Pearson's
+                           'log',      # G-test (log-likelihood)
+                           'mod_log',  # Modified log-likelihood
+                           'cr',       # Cressie-Read (lambda=2/3)
+                          ])
 
 # The details of the first two elements in power_div_1d_cases are used
 # in a test in TestPowerDivergence.  Check that code before making