Fix api_endpoints() view for DS

[IonesioJunior]

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[eelcovdw]

One style comment, rest looks good to go!

[eelcovdw]

Would prefer to keep the NOT_ACCESSIBLE_STRING only to the repr methods, and have self.mock_function be None if it is not defined:

if self.mock_function is None:
    mock_function_name = NOT_ACCESSIBLE_STRING
else:
    # parse function name

Same in api.py:562

That would clear the logic here up a lot I think

[IonesioJunior]

Solved by: b56b3e1