<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:

def get_return_page(self,prior=False):
        ''' This is just a wrapper for the getReturnPage helper function. '''
        siteHistory = self.request.session.get('SITE_HISTORY',{})
        return getReturnPage(siteHistory,prior=prior)