Set the default starting HTML header level for structured text documents. The default is 3, which implies that top-level headers will be created with an H3 HTML tag.

设置结构化文本文档HTML标题级别。默认为3，这就意味着最高级别的标题会被打上H3 HTML标签。

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Clarke, who works as a poet, playwright, editor, creative writing tutor and translator is well known in schools across the UK as a set-text poet for GCSE and A-level English.

BBC: Clarke named Wales' national poet