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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def shell_add_echo(script):
 """Goes over each line script, adds "echo cmd" in front of each cmd. ls a becomes echo * ls a ls a """

  new_script = ""
  for cmd in script.split('\n'):
    cmd = cmd.strip()
    if not cmd:
      continue
    new_script += "echo \\* " + shlex.quote(cmd) + "\n"
    new_script += cmd + "\n"
  return new_script