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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 changed(self, *fields):
 """Test if one or more fields have changed. A field is considered to have changed if it has been marked as changed, or if any of its parent, or child, fields have been marked as changed. """

        S = super(Value, self).changed
        for fld in fields or (None,): # no args tests for any change
            if S(fld):
                return True
        return False