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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_credentials(username: str = None, **kwargs) -> dict: """ Calculate credentials for Axes to use internally from given username and kwargs. Axes will set the username value into the key defined with ``settings.AXES_USERNAME_FORM_FIELD`` and update the credentials dictionary with the kwargs given on top of that. """


    credentials = {settings.AXES_USERNAME_FORM_FIELD: username}
    credentials.update(kwargs)
    return credentials