def METHOD_NAME(self):
    """
    If the endpoint has no 'produces' then the default is
    'application/json'.
    :rtype str
    """
    # TODO: don't default
    if all_json(self.produces):
        try:
            return self.produces[0]
        except IndexError:
            return DEFAULT_MIMETYPE
    elif len(self.produces) == 1:
        return self.produces[0]
    else:
        return DEFAULT_MIMETYPE