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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 main(jlink_serial, device):
 """Prints the core's information. Args: jlink_serial (str):
 the J-Link serial number device (str):
 the target CPU Returns: Always returns ``0``. Raises: JLinkException: on error """

    buf = StringIO.StringIO()
    jlink = pylink.JLink(log=buf.write, detailed_log=buf.write)
    jlink.open(serial_no=jlink_serial)

    # Use Serial Wire Debug as the target interface.
    jlink.set_tif(pylink.enums.JLinkInterfaces.SWD)
    jlink.connect(device, verbose=True)

    sys.stdout.write('ARM Id: %d\n' % jlink.core_id())
    sys.stdout.write('CPU Id: %d\n' % jlink.core_cpu())
    sys.stdout.write('Core Name: %s\n' % jlink.core_name())
    sys.stdout.write('Device Family: %d\n' % jlink.device_family())