How to open mat-select after load data?

I have tied to open select list after data was loaded:

   <mat-form-field (click)="choose()">
        <mat-select #mySelect multiple>Here empty list by default</mat-select>
    </mat-form-field>
      

Component

@ViewChild('mySelect', { static: true }) mySelect: MatSelect;

choose() {
   this.employService.get(this.depid).subscribe((response) => {
      this.mySelect.open();
   });
}

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Source Url How to open mat-select after load data?