input: Write a function to calculate the distance between two points on a two-dimensional plane. The function should take two tuples as inputs, where each tuple contains the coordinates (x, y) for each point. Use the Euclidean distance formula to compute the distance. If the input tuples are empty, return 0.0.
  assert calculate_distance((3, 4), (-9, -2)) == 13.45362404707371
  assert calculate_distance((0, 0), (0, 0)) == 0.0
  assert calculate_distance((1, 2), (4, 6)) == 5.0
  assert calculate_distance((7, 9), (3, 7)) == 4.47213595499958
  assert calculate_distance((), ()) == 0.0
output: def calculate_distance(point1, point2):
      if not point1 or not point2:
          return 0.0
      x1, y1 = point1
      x2, y2 = point2
      return ((x2 - x1) ** 2 + (y2 - y1) ** 2) ** 0.5