a method to remove all records in the collection

        NOTE:   this method removes all the files in the collection, but the
                collection folder itself created by oauth2 cannot be removed.
                only the user can remove access to the app folder
                
        :return: string with confirmation of deletion

def remove(self):
        
        ''' 
            a method to remove all records in the collection

        NOTE:   this method removes all the files in the collection, but the
                collection folder itself created by oauth2 cannot be removed.
                only the user can remove access to the app folder
                
        :return: string with confirmation of deletion
        '''

        title = '%s.remove' % self.__class__.__name__
    
    # get contents of root
        for id, name, mimetype in self._list_directory():
            try:
                self.drive.delete(fileId=id).execute()
            except Exception as err:
                if str(err).find('File not found') > -1:
                    pass
                else:
                    raise DriveConnectionError(title)
    
    # return outcome
        insert = 'collection'
        if self.collection_name:
            insert = self.collection_name
        exit_msg = 'Contents of %s will be removed from Google Drive.' % insert
        return exit_msg