input: Write a python function to measure the execution time of a given function using a decorator.
  assert measure_time(lambda: time.sleep(1))==None
  assert measure_time(lambda: sum(range(1000000)))==None
  assert measure_time(lambda: [i**2 for i in range(1000)])==None
output: import time
  
  def measure_time(func):
      def wrapper():
          start_time = time.time()
          result = func()
          end_time = time.time()
          print(f"Execution time: {end_time - start_time} seconds")
          return result
      return wrapper
  
  @measure_time
  def lambda_func():
      return func()
  
  @measure_time
  def lambda_func():
      return func()
  
  @measure_time
  def lambda_func():
      return func()