Work around python/mypy#9940

Author: khaeru

setup.cfg

@@ -73,6 +73,10 @@ use_parentheses = True
 [flake8]
 max-line-length = 88
 
+[mypy]
+# Empty section required as of mypy 0.800;
+# see https://github.com/python/mypy/issues/9940
+
 [mypy-asyncssh.*]
 ignore_missing_imports = True
 [mypy-ixmp.*]