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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 save(obj=None, m2m_data=None):
 """Saves a deserialized model object. Uses save_base to avoid running code in model.save() and to avoid triggering signals (if raw=True). """

    m2m_data = {} if m2m_data is None else m2m_data
    obj.save_base(raw=True)
    for attr, values in m2m_data.items():
        for value in values:
            getattr(obj, attr).add(value)