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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 _replace_file(path, content):
 """Writes a file if it doesn't already exist with the same content. This is useful because cargo uses timestamps to decide whether to compile things."""

  if os.path.exists(path):
    with open(path, 'r') as f:
      if content == f.read():
        print("Not overwriting {} because it is unchanged".format(path), file=sys.stderr)
        return

  with open(path, 'w') as f:
    f.write(content)