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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 get_prefix(self, form, name):
 """ Return the prefix that is used for the formset. """

        return '{form_prefix}{prefix_name}-{field_name}'.format(
            form_prefix=form.prefix + '-' if form.prefix else '',
            prefix_name=self.prefix_name,
            field_name=name)