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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 remove_css_class(css_classes, css_class):
 """ Remove a CSS class from a string of CSS classes """

    remove = set(split_css_classes(css_class))
    classes_list = [c for c in split_css_classes(css_classes) if c not in remove]
    return " ".join(classes_list)