#' @import htmltools
#' @export tags p h1 h2 h3 h4 h5 h6 a br div span pre code img strong em hr
#' @export tag tagList tagAppendAttributes tagHasAttribute tagGetAttribute tagAppendChild tagAppendChildren tagSetChildren
#' @export HTML
#' @export includeHTML includeText includeMarkdown includeCSS includeScript
#' @export singleton is.singleton
#' @export validateCssUnit
#' @export htmlTemplate
#' @export suppressDependencies
#' @export withTags
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