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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 _create(self, rawtitle):
 """Create a page with this title, if it doesn't exist. This method first checks whether a page with the same slug (sanitized name) exists_on_disk. If it does, it doesn't do antyhing. Otherwise, the relevant attributes are created. Nothing is written to disc (to the source file). You must call the write_page method to do that. Doing it this way, after creation you can call a method to add random text, for example, before committing the page to disk. """

        slug = util.make_slug(rawtitle)
        if self.site.page_exists_on_disk(slug):
            raise ValueError
            #print "Attempted to create a page which already exists."
            #return False

        self._title = unicode(rawtitle,"UTF-8")
        self._slug = slug

        self._dirs['source_dir'] = os.path.join(self.site.dirs['source'], slug)
        self._dirs['source_filename'] = os.path.join(self._dirs['source_dir'],
                                                     slug + '.md')

        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')
        self._config = self._create_config()
        return True