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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 _init():
 """ build connection and init it"""

    connection.connect()

    # start track
    # all services were provided here:
    # https://android.googlesource.com/platform/system/core/+/jb-dev/adb/SERVICES.TXT
    ready_data = utils.encode_data('host:track-devices')
    connection.adb_socket.send(ready_data)

    # get status
    status = connection.adb_socket.recv(4)

    # make sure track is ready
    if status != b'OKAY':
        raise RuntimeError('adb server return "{}", not OKAY'.format(str(status)))