input: from typing import Tuple
  
  def objective_function(a: float, b: float, c: float, x: float, y: float) -> float:
      """
      Calculate the objective function of a linear equation in the form ax + by = c.
      
      >>> objective_function(3, 5, 7, 1, 1)
      linear_eq(3, 5, 7)
      
      >>> objective_function(1, 1, 1, 2, 3)
      linear_eq(1, 1, 1)
      """
      def linear_eq(a, b, c):
          return a*x + b*y - c
      return linear_eq(a, b, c)
output:     def linear_eq(a, b, c):
          return a*x + b*y - c
      return linear_eq(a, b, c)