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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 delete_all(self, filter=None, timeout=-1):
 """ Delete an SNMPv3 User based on User name specified in filter. The user will be deleted only if it has no associated destinations. Args: username: ID or URI of SNMPv3 user. filter: A general filter/query string to narrow the list of items returned. The default is no filter - all resources are returned. Returns: bool: Indicates if the resource was successfully deleted. """

        return self._client.delete_all(filter=filter, timeout=timeout)