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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 get_desktop_env():
 """Identify the current running desktop environment."""

    desktop = os.environ.get("XDG_CURRENT_DESKTOP")
    if desktop:
        return desktop

    desktop = os.environ.get("DESKTOP_SESSION")
    if desktop:
        return desktop

    desktop = os.environ.get("GNOME_DESKTOP_SESSION_ID")
    if desktop:
        return "GNOME"

    desktop = os.environ.get("MATE_DESKTOP_SESSION_ID")
    if desktop:
        return "MATE"

    desktop = os.environ.get("SWAYSOCK")
    if desktop:
        return "SWAY"

    desktop = os.environ.get("DESKTOP_STARTUP_ID")
    if desktop and "awesome" in desktop:
        return "AWESOME"

    return None