input: Write a python function to calculate GDP from consumption, investment, government spending, export, and import.
  assert calculate_GDP(100, 50, 25, 20, 10) == 185
  assert calculate_GDP(200, 100, 50, 30, 20) == 360
  assert calculate_GDP(150, 60, 40, 25, 15) == 260
output: def calculate_GDP(consumption, investment, government_spending, export, import_):
      return consumption + investment + government_spending + (export - import_)