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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 post(self, request, **resources):
 """ Default POST method. Uses the handler's form. :return object: saved instance or raise form's error """

        if not self._meta.form:
            return None

        form = self._meta.form(request.data, **resources)
        if form.is_valid():
            return form.save()

        raise FormError(form)