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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 method_call_if_def(obj, attr_name, m_name, default, *args, **kwargs):
 """Calls the provided method if it is defined. Returns default if not defined. """

    try:
        attr = getattr(obj, attr_name)
    except AttributeError:
        return default
    else:
        return getattr(attr, m_name)(*args, **kwargs)