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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 parse(theme_file):
 """Parse the theme file."""

    data = util.read_file_json(theme_file)

    if "wallpaper" not in data:
        data["wallpaper"] = "None"

    if "alpha" not in data:
        data["alpha"] = util.Color.alpha_num

    # Terminal.sexy format.
    if "color" in data:
        data = terminal_sexy_to_wal(data)

    return data