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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 form_valid(self, form):
 """Pull the metrics from the submitted form, and store them as a list of strings in ``self.metric_slugs``. """

        self.metric_slugs = [k.strip() for k in form.cleaned_data['metrics']]
        return super(AggregateFormView, self).form_valid(form)