With the default reStructuredText format, PyCharm highlights words such as param, type, raise, and return, such as in the example below:
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However, when I try another style such as Google, none of the docstring stub generated is similarly highlighted.
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I went to settings > Tools > Python Integrated Tools > Docstrings and changed Docstring format to various styles included by default like Numpy and Google, but only reStructuredText has docstring highlighting.