How to use the node-opcua-service-endpoints.UserTokenType.UserName function in node-opcua-service-endpoints

securityPolicyUri: SecurityPolicy.Basic256Sha256
        });

        userIdentityTokens.push({
            policyId: "certificate_basic256Sha256",
            tokenType: UserTokenType.Certificate,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: SecurityPolicy.Basic256Sha256
        });

        // X509
        userIdentityTokens.push({
            policyId: "certificate_basic256",
            tokenType: UserTokenType.UserName,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: SecurityPolicy.Basic256
        });

        userIdentityTokens.push({
            policyId: "certificate_basic128",
            tokenType: UserTokenType.UserName,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: SecurityPolicy.Basic128Rsa15
        });

        userIdentityTokens.push({

securityPolicyUri: SecurityPolicy.Basic256Sha256
        });

        // X509
        userIdentityTokens.push({
            policyId: "certificate_basic256",
            tokenType: UserTokenType.UserName,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: SecurityPolicy.Basic256
        });

        userIdentityTokens.push({
            policyId: "certificate_basic128",
            tokenType: UserTokenType.UserName,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: SecurityPolicy.Basic128Rsa15
        });

        userIdentityTokens.push({
            policyId: "certificate_basic256Sha256",
            tokenType: UserTokenType.UserName,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: SecurityPolicy.Basic256Sha256
        });

        userIdentityTokens.push({

securityPolicyUri: SecurityPolicy.Basic256Sha256
        });

        // X509
        userIdentityTokens.push({
            policyId: "certificate_basic256",
            tokenType: UserTokenType.UserName,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: SecurityPolicy.Basic256
        });

        userIdentityTokens.push({
            policyId: "certificate_basic128",
            tokenType: UserTokenType.UserName,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: SecurityPolicy.Basic128Rsa15
        });

        userIdentityTokens.push({
            policyId: "certificate_basic256Sha256",
            tokenType: UserTokenType.UserName,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: SecurityPolicy.Basic256Sha256
        });

        userIdentityTokens.push({

policyId: "certificate_basic256Sha256",
            tokenType: UserTokenType.Certificate,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: SecurityPolicy.Basic256Sha256
        });

    } else {
        // note:
        //  when channel session security is not "None",
        //  userIdentityTokens can be left to null.
        //  in this case this mean that secure policy will be the same as connection security policy
        userIdentityTokens.push({
            policyId: "usernamePassword",
            tokenType: UserTokenType.UserName,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: null
        });

        userIdentityTokens.push({
            policyId: "certificateX509",
            tokenType: UserTokenType.Certificate,

            issuedTokenType: null,
            issuerEndpointUrl: null,
            securityPolicyUri: null
        });

    }