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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 dbfpack(fn, usecols=None):
 """Return a ChannelPack instance loaded with dbf data file fn. This is a lazy function to get a loaded instance, using pulldbf module."""


    loadfunc = pulldbf.dbf_asdict
    cp = ChannelPack(loadfunc)
    cp.load(fn, usecols)
    names = pulldbf.channel_names(fn, usecols)
    cp.set_channel_names(names)
    # cp.set_basefilemtime()
    return cp