bufp := base64BufPool.Get().(*[]byte)
	defer base64BufPool.Put(bufp)

	tokenBuf := base64BufPool.Get().(*[]byte)
	defer base64BufPool.Put(tokenBuf)

	token := *tokenBuf
	// Copy token to buffer, truncate to length.
	token = token[:copy(token[:base64BufferSize], tokenStr)]

	signer, err := ParseUnverifiedStandardClaims(token, claims, *bufp)
	if err != nil {
		return err
	}

	i := bytes.LastIndexByte(token, '.')

// arguments.
type SimpleArgFunc struct {
	FunctionName string `parser:" @(\"AVG\" | \"MAX\" | \"MIN\" | \"SUM\" |  \"COALESCE\" | \"NULLIF\" | \"TO_STRING\" | \"TO_TIMESTAMP\" | \"UTCNOW\" | \"CHAR_LENGTH\" | \"CHARACTER_LENGTH\" | \"LOWER\" | \"UPPER\") "`

	ArgsList []*Expression `parser:"\"(\" (@@ (\",\" @@)*)?\")\""`
}

// CountFunc represents the COUNT sql function
type CountFunc struct {