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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 find(cls, name):
 """Returns the NDS2 channel type corresponding to the given name """

        try:
            return cls._member_map_[name]
        except KeyError:
            for ctype in cls._member_map_.values():
                if ctype.name == name:
                    return ctype
            raise ValueError('%s is not a valid %s' % (name, cls.__name__))