a method to retrieve details about a meetup group

        :param group_url: string with meetup urlname of group
        :param group_id: int with meetup id for group
        :return: dictionary with group details inside [json] key

        group_details = self._reconstruct_group(**{})

def get_group_details(self, group_url='', group_id=0):

        ''' a method to retrieve details about a meetup group

        :param group_url: string with meetup urlname of group
        :param group_id: int with meetup id for group
        :return: dictionary with group details inside [json] key

        group_details = self._reconstruct_group(**{})
        '''

    # https://www.meetup.com/meetup_api/docs/:urlname/#get

        title = '%s.get_group_details' % self.__class__.__name__

    # validate inputs
        input_fields = {
            'group_url': group_url,
            'group_id': group_id
        }
        for key, value in input_fields.items():
            if value:
                object_title = '%s(%s=%s)' % (title, key, str(value))
                self.fields.validate(value, '.%s' % key, object_title)
        if not group_url and not group_id:
            raise IndexError('%s requires either a group_url or group_id argument.' % title)

    # construct request fields
        if group_id:
            url = '%s/2/groups?fields=last_event,next_event,join_info&group_id=%s' % (self.endpoint, group_id)
        else:
            url = '%s/%s?fields=last_event,next_event,join_info' % (self.endpoint, group_url)

    # send request
        group_details = self._get_request(url)

    # cosntruct method output
        if group_id:
            if 'results' in group_details['json'].keys():
                if group_details['json']['results']:
                    group_details['json'] = self._reconstruct_group(group_details['json']['results'][0])
        else:
            group_details['json'] = self._reconstruct_group(group_details['json'])

        return group_details