PyCharm type hints

For class variables that get assigned:

def foo():
#: :type: ObservablePlanarGraph
self._graph = graph

For input variables (in a docstring):

def foo(self, feature_finder):
"""
:type feature_finder FeatureFinder
"""

For return types (also note, tuples and lists):

def foo(self):
"""
:rtype (list[PolicyData], list[PolicyData])
"""

return res