text: import pytest
  
  import python_lifecycle_training
  from python_lifecycle_training.calculator.complex import Calculator
  
  
  class TestCalculator:
      @staticmethod
      def test_add():
          assert Calculator.add(1, 2) == 3
  
      @staticmethod
      def test_sub():
          assert Calculator.sub(2, 1) == 1
  
      @staticmethod
      def test_mul():
          assert Calculator.mul(1, 2) == 2
  
      @staticmethod
      @pytest.mark.parametrize(
          "a, b",
          [
              (2, 1),
              (2, 0),
          ],
      )
      def test_div(a, b):
          if b != 0:
              assert Calculator.div(a, b) == pytest.approx(a / b)
          else:
              python_lifecycle_training.ENV = "development"
              with pytest.raises(ZeroDivisionError) as excinfo:
                  assert Calculator.div(a, b) is None
              assert str(excinfo.value) == "division by zero"
  
              python_lifecycle_training.ENV = "production"
              with pytest.warns(RuntimeWarning) as record:
                  assert Calculator.div(a, b) == 0
              assert str(record[0].message) == "division by zero"
  