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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 _check_data(wavfile, station, channel, debug=0):
 """ Inner loop for parallel checks. :type wavfile: str :param wavfile: Wavefile path name to look in. :type station: str :param station: Channel name to check for :type channel: str :param channel: Channel name to check for :type debug: int :param debug: Debug level, if > 1, will output what it it working on. """

    if debug > 1:
        print('Checking ' + wavfile)
    st = read(wavfile, headonly=True)
    for tr in st:
        if tr.stats.station == station and tr.stats.channel == channel:
            return wavfile