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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 global_custom_theme(request):
 """Add custom theme javascript and css."""

    today = datetime.datetime.now().date()
    theme = {}

    if today.month == 3 and (14 <= today.day <= 16):
        theme = {"css": "themes/piday/piday.css"}

    return {"theme": theme}