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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 render_category(category='', template=None):
 """ Render a category page. Arguments: category -- The category to render template -- The template to render it with """

    # pylint:disable=too-many-return-statements

    # See if this is an aliased path
    redir = get_redirect()
    if redir:
        return redir

    # Forbidden template types
    if template and template.startswith('_'):
        raise http_error.Forbidden("Template is private")
    if template in ['entry', 'error']:
        raise http_error.BadRequest("Invalid view requested")

    if category:
        # See if there's any entries for the view...
        if not orm.select(e for e in model.Entry if e.category == category or
                          e.category.startswith(category + '/')):
            raise http_error.NotFound("No such category")

    if not template:
        template = Category(category).get('Index-Template') or 'index'

    tmpl = map_template(category, template)

    if not tmpl:
        # this might actually be a malformed category URL
        test_path = '/'.join((category, template)) if category else template
        logger.debug("Checking for malformed category %s", test_path)
        record = orm.select(
            e for e in model.Entry if e.category == test_path).exists()
        if record:
            return redirect(url_for('category', category=test_path, **request.args))

        # nope, we just don't know what this is
        raise http_error.NotFound("No such view")

    view_spec = view.parse_view_spec(request.args)
    view_spec['category'] = category
    view_obj = view.View(view_spec)

    rendered, etag = render_publ_template(
        tmpl,
        _url_root=request.url_root,
        category=Category(category),
        view=view_obj)

    if request.if_none_match.contains(etag):
        return 'Not modified', 304

    return rendered, {'Content-Type': mime_type(tmpl),
                      'ETag': etag}