'Returns a twitter.User instance if the authenticating user is valid.
Returns:
A twitter.User instance representing that user if the
credentials are valid, None otherwise.'

def VerifyCredentials(self):

    url = ('%s/account/verify_credentials.json' % self.base_url)
    resp = self._RequestUrl(url, 'GET')
    data = self._ParseAndCheckTwitter(resp.content.decode('utf-8'))
    return User.NewFromJsonDict(data)
