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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 cp(src_filename, dst_filename):
 """Copies one file to another. The source file may be local or remote and the destination file may be local or remote. """

    src_dev, src_dev_filename = get_dev_and_path(src_filename)
    dst_dev, dst_dev_filename = get_dev_and_path(dst_filename)
    if src_dev is dst_dev:
        # src and dst are either on the same remote, or both are on the host
        return auto(copy_file, src_filename, dst_dev_filename)

    filesize = auto(get_filesize, src_filename)

    if dst_dev is None:
        # Copying from remote to host
        with open(dst_dev_filename, 'wb') as dst_file:
            return src_dev.remote(send_file_to_host, src_dev_filename, dst_file,
                                  filesize, xfer_func=recv_file_from_remote)
    if src_dev is None:
        # Copying from host to remote
        with open(src_dev_filename, 'rb') as src_file:
            return dst_dev.remote(recv_file_from_host, src_file, dst_dev_filename,
                                  filesize, xfer_func=send_file_to_remote)

    # Copying from remote A to remote B. We first copy the file
    # from remote A to the host and then from the host to remote B
    host_temp_file = tempfile.TemporaryFile()
    if src_dev.remote(send_file_to_host, src_dev_filename, host_temp_file,
                      filesize, xfer_func=recv_file_from_remote):
        host_temp_file.seek(0)
        return dst_dev.remote(recv_file_from_host, host_temp_file, dst_dev_filename,
                              filesize, xfer_func=send_file_to_remote)
    return False