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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 register(explicit=True):
 """ Register Pandas Formatters and Converters with matplotlib This function modifies the global ``matplotlib.units.registry`` dictionary. Pandas adds custom converters for * pd.Timestamp * pd.Period * np.datetime64 * datetime.datetime * datetime.date * datetime.time See Also -------- deregister_matplotlib_converter """

    # Renamed in pandas.plotting.__init__
    global _WARN

    if explicit:
        _WARN = False

    pairs = get_pairs()
    for type_, cls in pairs:
        converter = cls()
        if type_ in units.registry:
            previous = units.registry[type_]
            _mpl_units[type_] = previous
        units.registry[type_] = converter