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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 handle_valid(self, form=None, *args, **kwargs):
 """ Called after the form has validated. """

        # Take a chance and try save a subclass of a ModelForm.
        if hasattr(form, 'save'):
            form.save()
        # Also try and call handle_valid method of the form itself.
        if hasattr(form, 'handle_valid'):
            form.handle_valid(*args, **kwargs)