input: Write a function to evaluate a mathematical expression given as a string.
  assert evaluate_expression("2 + 3 * 5") == 17
  assert evaluate_expression("10 / 2 + 3") == 8.0
  assert evaluate_expression("100 - 5 * 2") == 90
output: def evaluate_expression(expression: str) -> float:
      return eval(expression)