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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 decode_body(cls, header, f):
 """Generates a `MqttPingresp` packet given a `MqttFixedHeader`. This method asserts that header.packet_type is `pingresp`. Parameters header: MqttFixedHeader f: file Object with a read method. Raises ------ DecodeError When there are extra bytes at the end of the packet. Returns ------- int Number of bytes consumed from ``f``. MqttPingresp Object extracted from ``f``. """

        assert header.packet_type == MqttControlPacketType.pingresp

        if header.remaining_len != 0:
            raise DecodeError('Extra bytes at end of packet.')

        return 0, MqttPingresp()