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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 _get_enum(name):
 """Get an existing enum ID"""

    eid = idaapi.get_enum(name)
    if eid == idaapi.BADADDR:
        raise exceptions.EnumNotFound('Enum "{}" does not exist.'.format(name))
    return eid