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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_form():
 """ Return the form to use for commenting. """

    global form_class
    from fluent_comments import appsettings
    if form_class is None:
        if appsettings.FLUENT_COMMENTS_FORM_CLASS:
            from django.utils.module_loading import import_string
            form_class = import_string(appsettings.FLUENT_COMMENTS_FORM_CLASS)
        else:
            from fluent_comments.forms import FluentCommentForm
            form_class = FluentCommentForm

    return form_class