func_code: def distance(x1, y1, x2, y2):
      disx = (x2 - x1) ** 2
      disy = (y2 - y1) ** 2
      dist = disx + disy
      return math.sqrt(dist)
  
  
  def overlap(x1=0, y1=0, r1=1, x2=0, y2=0, r2=1):
      if distance(x1, y1, x2, y2) < r1 + r2:
          return True
      else:
          return False