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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 list_locks(self, account_id=None):
 """Get extant locks for the given account. """

        account_id = self.get_account_id(account_id)
        return self.http.get(
            "%s/%s/locks" % (self.endpoint, account_id),
            auth=self.get_api_auth())