input: Write a function to calculate the square root of a user-defined positive number. If the number is not positive, raise a ValueError. The output should be formatted as "Square root of n is x", where n is the input number and x is the square root value.
  
  def square_root_calculator(n):
      if n <= 0:
          raise ValueError("Input must be a positive number.")
      x = math.sqrt(n)
      return f'Square root of {n} is {x}'
  
  assert square_root_calculator(100) == 'Square root of 100 is 10.0'
  assert square_root_calculator(25) == 'Square root of 25 is 5.0'
  assert square_root_calculator(1) == 'Square root of 1 is 1.0'
  assert square_root_calculator(0.25) == 'Square root of 0.25 is 0.5'
  try:
      square_root_calculator(0)
  except ValueError as e:
      assert str(e) == "Input must be a positive number."
  try:
      square_root_calculator(-1)
  except ValueError as e:
      assert str(e) == "Input must be a positive number."
output: def square_root_calculator(n):
      if n <= 0:
          raise ValueError("Input must be a positive number.")
      x = math.sqrt(n)
      return f'Square root of {n} is {x}'