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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 search_prospects(self, search_type, query, offset=None, orgoffset=None):
 """ Supports doing a search for prospects by city, reion, or country. search_type should be one of 'city' 'region' 'country'. This method is intended to be called with one of the outputs from the get_options_for_query method above. """

        
        params = {'q': query}
        if offset and orgoffset:
            params['orgOffset'] = orgoffset
            params['timeOffset'] = offset
          
        return self._call('search/%s' % search_type, params)