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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_wcs(name, wrapper_class, coord_types):
 """ Register a custom WCS wrapper. Parameters name : str The name of the custom WCS wrapper wrapper_class : subclass of `~ginga.util.wcsmod.BaseWCS` The class implementing the WCS wrapper coord_types : list of str List of names of coordinate types supported by the WCS """

    global custom_wcs
    custom_wcs[name] = Bunch.Bunch(name=name,
                                   wrapper_class=wrapper_class,
                                   coord_types=coord_types)