How to use the distlib.locators.CHARSET.search function in distlib

# The `retrieve()` method follows any eventual redirects, so the
        # initial url might be different from the final one
        try:
            response, final_url = http_retrieve(self.opener, url)
        except urllib3.exceptions.MaxRetryError:
            return

        content_type = response.headers.get('content-type', '')
        if locators.HTML_CONTENT_TYPE.match(content_type):
            data = response.data
            encoding = response.headers.get('content-encoding')
            if encoding:
                decoder = self.decoders[encoding]   # fail if not found
                data = decoder(data)
            encoding = 'utf-8'
            m = locators.CHARSET.search(content_type)
            if m:
                encoding = m.group(1)
            try:
                data = data.decode(encoding)
            except UnicodeError:
                data = data.decode('latin-1')    # fallback
            return locators.Page(data, final_url)

# The `retrieve()` method follows any eventual redirects, so the
        # initial url might be different from the final one
        try:
            response, final_url = self.opener.retrieve(url)
        except urllib3.exceptions.MaxRetryError:
            return

        content_type = response.headers.get('content-type', '')
        if locators.HTML_CONTENT_TYPE.match(content_type):
            data = response.data
            encoding = response.headers.get('content-encoding')
            if encoding:
                decoder = self.decoders[encoding]   # fail if not found
                data = decoder(data)
            encoding = 'utf-8'
            m = locators.CHARSET.search(content_type)
            if m:
                encoding = m.group(1)
            try:
                data = data.decode(encoding)
            except UnicodeError:
                data = data.decode('latin-1')    # fallback
            return locators.Page(data, final_url)