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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_map_href(self):
 """ Returns a link to an external view of the map """

        if self.map_center_lat and self.map_center_long:
            params = {
                'll': '%s,%s' % (self.map_center_lat, self.map_center_long)
            }
        else:
            params = {'q': self.map_center_description}

        return self.GOOGLE_MAPS_HREF_ROOT + urllib.urlencode(params)