关于抓取回来的网页数据保存失败问题？？？

获取保存的页面数据

content = soup.find_all('div',{'class':'single-content'})

pymysqlcon = pymysql.connect(
        host='127.0.0.1',
        user='root',
        password='root',
        db='spider',
        charset="utf8mb4"
    )

try:
    with pymysqlcon.cursor() as cursor:
        sql = "insert into `content`(`content`) values(%s)"
        cursor.execute(sql,(content))
        pymysqlcon.commit()
finally:
    pymysqlcon.close()

报错以下：

Traceback (most recent call last):

  File "D:/pycharm/index.py", line 33, in <module>

    cursor.execute(sql,(content))

  File "D:\Python\lib\site-packages\pymysql\cursors.py", line 168, in execute

    query = self.mogrify(query, args)

  File "D:\Python\lib\site-packages\pymysql\cursors.py", line 147, in mogrify

    query = query % self._escape_args(args, conn)

  File "D:\Python\lib\site-packages\pymysql\cursors.py", line 122, in _escape_args

    return tuple(conn.literal(arg) for arg in args)

  File "D:\Python\lib\site-packages\pymysql\cursors.py", line 122, in <genexpr>

    return tuple(conn.literal(arg) for arg in args)

  File "D:\Python\lib\site-packages\pymysql\connections.py", line 846, in literal

    return self.escape(obj, self.encoders)

  File "D:\Python\lib\site-packages\pymysql\connections.py", line 839, in escape

    return converters.escape_item(obj, self.charset, mapping=mapping)

  File "D:\Python\lib\site-packages\pymysql\converters.py", line 27, in escape_item

    val = encoder(val, mapping)

  File "D:\Python\lib\site-packages\pymysql\converters.py", line 118, in escape_unicode

    return u"'%s'" % _escape_unicode(value)

  File "D:\Python\lib\site-packages\pymysql\converters.py", line 73, in _escape_unicode

    return value.translate(_escape_table)

TypeError: 'NoneType' object is not callable