You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: license.go
    path of file: ./repos/kin-openapi/openapi3
    
    the code of the file until where you have to start completion: package openapi3

import (
	"context"
	"encoding/json"
	"errors"
)

// License is specified by OpenAPI/Swagger standard version 3.
// See https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.0.3.md#license-object
type License struct {
	Extensions map[string]interface{} `json:"-" yaml:"-"`

	Name string `json:"name" yaml
    
func (license *License) UnmarshalJSON(data []byte) error {
	type LicenseBis License
	var x LicenseBis
	if err := json.Unmarshal(data, &x); err != nil {
		return unmarshalError(err)
	}
	_ = json.Unmarshal(data, &x.Extensions)
	delete(x.Extensions, "name")
	delete(x.Extensions, "url")
	if len(x.Extensions) == 0 {
		x.Extensions = nil
	}
	*license = License(x)
	return nil
}