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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 pagination_for(context, current_page, page_var="page", exclude_vars=""):
 """ Include the pagination template and data for persisting querystring in pagination links. Can also contain a comma separated string of var names in the current querystring to exclude from the pagination links, via the ``exclude_vars`` arg. """

    querystring = context["request"].GET.copy()
    exclude_vars = [v for v in exclude_vars.split(",") if v] + [page_var]
    for exclude_var in exclude_vars:
        if exclude_var in querystring:
            del querystring[exclude_var]
    querystring = querystring.urlencode()
    return {
        "current_page": current_page,
        "querystring": querystring,
        "page_var": page_var,
    }