input: from typing import List
  
  def calculate_sum_lambda(a: float, b: float) -> lambda:
      """ Suggest a valid Python syntax to calculate the sum of two variables using lambda
      >>> calculate_sum_lambda(3, 4)
      lambda a, b: a + b
      >>> print((lambda a, b: a + b)(3, 4))
      7
      """
output:     return lambda a, b: a + b