code: def check_overlap(current, hit, overlap = 200):
      
      for prev in current:
          p_coords = prev[2:4]
          coords = hit[2:4]
          if get_overlap(coords, p_coords) >= overlap:
              return True
      return False
docs: determine if sequence has already hit the same part of the model,
      indicating that this hit is for another 16S rRNA gene