input: Write a python function to execute a shell command and return its exit status.
  assert execute_shell_command('python script.py') == 0
  assert execute_shell_command('exit 1') == 1
  assert execute_shell_command('invalid_command') != 0
output: import subprocess
  
  def execute_shell_command(command):
      try:
          result = subprocess.run(command, shell=True)
          return result.returncode
      except Exception as e:
          return -1