return "PUT"
	case tierDelete:
		return "DELETE"
	}
	return "UNKNOWN"
}

type tierPermErr struct {
	Op  tierOp
	Err error
}

func (te tierPermErr) Error() string {
	return fmt.Sprintf("failed to perform %s: %v", te.Op, te.Err)
}

func errIsTierPermError(err error) bool {
	var tpErr tierPermErr
	return errors.As(err, &tpErr)
}

		expectedErrCode     APIErrorCode
	}{
		// Test Case - 1.
		// Test case with no '=' in te inputCredentialStr.
		{
			inputCredentialStr:  "Credential",
			expectedCredentials: credentialHeader{},
			expectedErrCode:     ErrMissingFields,
		},
		// Test Case - 2.
		// Test case with no "Credential" string in te inputCredentialStr.
		{
			inputCredentialStr:  "Cred=",
			expectedCredentials: credentialHeader{},