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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 alias_field(model, field):
 """ Return the prefix name of a field """

    for part in field.split(LOOKUP_SEP)[:-1]:
        model = associate_model(model,part)
    return model.__name__ + "-" + field.split(LOOKUP_SEP)[-1]