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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 call_html_collect_pages(cls, kb_app, sphinx_app: Sphinx):
 """ On html-collect-pages, do callbacks"""


        EventAction.get_callbacks(kb_app,
                                  SphinxEvent.HCP)
        for callback in EventAction.get_callbacks(kb_app,
                                                  SphinxEvent.HCP):
            yield callback(kb_app, sphinx_app)