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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 get_protocol(handle: Handle, want_v2: bool) -> Protocol: """Make a Protocol instance for the given handle. Each transport can have a preference for using a particular protocol version. This preference is overridable through `TREZOR_PROTOCOL_V1` environment variable, which forces the library to use V1 anyways. As of 11/2018, no devices support V2, so we enforce V1 here. It is still possible to set `TREZOR_PROTOCOL_V1=0` and thus enable V2 protocol for transports that ask for it (i.e., USB transports for Trezor T). """

    force_v1 = int(os.environ.get("TREZOR_PROTOCOL_V1", 1))
    if want_v2 and not force_v1:
        return ProtocolV2(handle)
    else:
        return ProtocolV1(handle)