def example_function(param='param'):
    """
    Prints hello world and returns param.
    Good link on how to write these napolean docs:
    https://sphinxcontrib-napoleon.readthedocs.io/en/latest/

    Parameters
    ----------
    param
        A string to be prtined. Very creative.

    Returns
    -------
    string
        Whatever param is set to.
    """
    print('Hello world')
    return param
