'Adds the session cookie to headers.'

def save(self):

    if self.data:
        cookie = self.create_cookie()
        cookie_len = len(cookie)
        if (cookie_len > 4093):
            raise SessionError('Cookie    too    long!    The    cookie    size    {0}    is    more    than    4093    bytes.'.format(cookie_len))
        self.adapter.set_header('Set-Cookie', cookie)
        self._data = {}
