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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 _css_select(soup, css_selector):
 """ Returns the content of the element pointed by the CSS selector, or an empty string if not found """

        selection = soup.select(css_selector)
        if len(selection) > 0:
            if hasattr(selection[0], 'text'):
                retour = selection[0].text.strip()
            else:
                retour = ""
        else:
            retour = ""
        return retour