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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 deregister():
 """ Remove pandas' formatters and converters Removes the custom converters added by :func:`register`. This attempts to set the state of the registry back to the state before pandas registered its own units. Converters for pandas' own types like Timestamp and Period are removed completely. Converters for types pandas overwrites, like ``datetime.datetime``, are restored to their original value. See Also -------- deregister_matplotlib_converters """

    # Renamed in pandas.plotting.__init__
    for type_, cls in get_pairs():
        # We use type to catch our classes directly, no inheritance
        if type(units.registry.get(type_)) is cls:
            units.registry.pop(type_)

    # restore the old keys
    for unit, formatter in _mpl_units.items():
        if type(formatter) not in {DatetimeConverter, PeriodConverter,
                                   TimeConverter}:
            # make it idempotent by excluding ours.
            units.registry[unit] = formatter