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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_context_data(self, **kwargs):
        ''' Add the list of registrations for the given series '''

        # Update the site session data so that registration processes know to send return links to
        # the view class registrations page.  set_return_page() is in SiteHistoryMixin.
        self.set_return_page('viewregistrations',_('View Registrations'),event_id=self.object.id)

        context = {
            'event': self.object,
            'registrations': EventRegistration.objects.filter(
                event=self.object,
                cancelled=False
            ).order_by('registration__customer__user__first_name', 'registration__customer__user__last_name'),
        }
        context.update(kwargs)
        return super(EventRegistrationSummaryView, self).get_context_data(**context)