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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 get_beautiful_soup(self, source=None):
 """ BeautifulSoup is a toolkit for dissecting an HTML document and extracting what you need. It's great for screen-scraping! """

        from bs4 import BeautifulSoup
        if not source:
            self.wait_for_ready_state_complete()
            source = self.get_page_source()
        soup = BeautifulSoup(source, "html.parser")
        return soup