input: Write a function to calculate the distance between two points on a two-dimensional plane. The function should take four inputs: the x and y coordinates of the first point and the x and y coordinates of the second point. The function should return the distance between these two points as a float.
  
  assert calculate_distance(3, 4, -9, -2) == 13.0
  assert calculate_distance(0, 0, 0, 0) == 0.0
  assert calculate_distance(1, 1, 4, 5) == 5.0
  assert calculate_distance(-3, 2, 3, -1) == 6.7082
  assert calculate_distance(-7, -8, 2, 6) == 14.866
output: def calculate_distance(x1, y1, x2, y2):
      return ((x2 - x1) ** 2 + (y2 - y1) ** 2) ** 0.5