input: Write a function to calculate the square root of a user-defined positive number. The function should return the square root of the given number. If the number is negative, the function should return an error message.
  assert calculate_square_root(100)==10.0
  assert calculate_square_root(25)==5.0
  assert calculate_square_root(0)==0.0
  assert calculate_square_root(-10)=="Error: Negative numbers are not allowed"
output: def calculate_square_root(number):
      if number < 0:
          return "Error: Negative numbers are not allowed"
      return number ** 0.5