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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 _load(self, slug):
 """Load the page. The _file_name param is known, because this method is only called after having checked that the page exists. """

        #here we know that the slug exists
        self._slug = slug
        page_dir = os.path.join(self.site.dirs['source'], self._slug)
        page_file_name = os.path.join(page_dir, self._slug + '.md')
        self._dirs['source_dir'] = page_dir
        self._dirs['source_filename'] = page_file_name
        self._dirs['www_dir'] = os.path.join(self.site.dirs['www'], slug)
        self._dirs['www_filename'] = os.path.join(self._dirs['www_dir'],  'index.html')

        #pf = open(self._dirs['source_filename'], 'r')
        #page_text = pf.read()
        #pf.close()
        # need to decode!
        pf = codecs.open(self._dirs['source_filename'], mode="r", encoding="utf-8")
        page_text = pf.read()
        pf.close()

        self._parse_text(page_text)
        if not self._check_config():
            raise ValueError
            #sys.exit()
        self._title = self._config['title'][0]