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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 uploaded_filepath(instance, filename):
 """ Returns default filepath for uploaded files. """

    ext = filename.split('.')[-1]
    filename = "%s.%s" % (uuid.uuid4(), ext)
    today = datetime.now().strftime('%Y-%m-%d')
    return os.path.join('django-summernote', today, filename)