def flat_cover(self, minAcc, maxAcc, groupBy=None, new_reg_fields=None):
        """
        *Wrapper of* ``COVER``

        Variant of the function :meth:`~.cover` that returns the union of all the regions 
        which contribute to the COVER. More precisely, it returns the contiguous regions 
        that start from the first end and stop at the last end of the regions which would 
        contribute to each region of a COVER.
        
        Equivalent to calling::
        
            cover("flat", ...)
        """
        return self.cover(minAcc, maxAcc, groupBy, new_reg_fields, cover_type="flat")