Vue typescript

Question

我在Vue项目里用了typescript,引用了ant-desigb-vue的from组件

<script lang="ts">
import { Component, Vue } from 'vue-property-decorator';
function hasErrors (fieldsError :any) {
  return Object.keys(fieldsError).some(field => fieldsError[field]);
}
@Component({
  components: {},
  data () {
    return {
      hasErrors,
      form: this.$form.createForm(this),
    };
  },
  mounted () {
    this.$nextTick(() => {
      // To disabled submit button at the beginning.
      this.form.validateFields();
    });
  },
  methods: {
    // Only show error after a field is touched.
    userNameError () {
      const { getFieldError, isFieldTouched } = this.form;
      return isFieldTouched('userName') && getFieldError('userName');
    },
    // Only show error after a field is touched.
    passwordError () {
      const { getFieldError, isFieldTouched } = this.form;
      return isFieldTouched('password') && getFieldError('password');
    },
    handleSubmit  (e) {
      e.preventDefault();
      this.form.validateFields((err: any, values: any) => {
        if (!err) {
          console.log('Received values of form: ', values);
        }
      });
    },
  },
  created(){
    console.log(this.form);
  }
})
export default class Home extends Vue {}
</script>

组件是正常运行的，就是typescript会报错：

Property 'form' does not exist on type 'Vue'. Did you 
mean '$form'?

怎么解？我在created打印this.form也可以打印出来啊，怎么解决这个typescript错误？
typescript新手 求教