code: def smooth_gaps(self,min_intron):
      
      rngs = [self._rngs[0].copy()]
      for i in range(len(self._rngs)-1):
        dist = -1
        if self._rngs[i+1].chr == rngs[-1].chr:
          dist = self._rngs[i+1].start - rngs[-1].end-1
        if dist >= min_intron or dist < 0:
          rngs.append(self._rngs[i+1].copy())
        else:
          rngs[-1].end = self._rngs[i+1].end
      return type(self)(rngs,self._options)
docs: any gaps smaller than min_intron are joined, andreturns a new mapping with gaps smoothed
  
      :param min_intron: the smallest an intron can be, smaller gaps will be sealed
      :type min_intron: int
      :return: a mapping with small gaps closed
      :rtype: MappingGeneric