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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 all(self, page=None, per_page=None, include_totals=False, extra_params=None):
 """Retrieves all grants. Args: page (int, optional):
 The result's page number (zero based). per_page (int, optional):
 The amount of entries per page. include_totals (bool, optional):
 True if the query summary is to be included in the result, False otherwise. extra_params (dictionary, optional):
 The extra parameters to add to the request. The page, per_page, and include_totals values specified as parameters take precedence over the ones defined here. See: https://auth0.com/docs/api/management/v2#!/Grants/get_grants """

        params = extra_params or {}
        params.update({
            'page': page,
            'per_page': per_page,
            'include_totals': str(include_totals).lower()
        })

        return self.client.get(self._url(), params=params)