Set mypy to >=0.710,<0.8 (#286)

Author: fabaff

setup.py

@@ -99,7 +99,7 @@ def get_git_commit_datetime() -> str:
     'flake8-docstrings==1.3.0',
     'flake8==3.7.7',
     'mock-open==1.3.1',
-    'mypy==0.701',
+    'mypy>=0.710,<0.8',
     'pydocstyle==3.0.0',
     'pylint==2.3.1',
     'pytest-cov==2.6.1',