input: Write a python function to execute a Python file from the command line.
  assert execute_python_file("test.py") is None
  assert execute_python_file("nonexistent.py") is None
output: def execute_python_file(filename):
      import subprocess
      try:
          subprocess.run(['python', filename], check=True)
      except FileNotFoundError:
          pass
      except subprocess.CalledProcessError:
          pass