code: func NewAssertContext(options ...AssertContextConfigOption) AssertContext {
  	expectedString := GenerateRandomString()
  
  	serviceAccountFile := os.Getenv(ServiceAccountFileEnv)
  	Expect(serviceAccountFile).ToNot(BeEmpty(),
  		fmt.Sprintf(ServiceAccountFileMsg, ServiceAccountFileEnv))
  
  	return AssertContext{
  		ExpectedString:     expectedString,
  		ContentFile:        MakeContentFile(expectedString),
  		GCSFileName:        GenerateRandomString(),
  		serviceAccountFile: serviceAccountFile,
  		options:            options,
  		ctx:                context.Background(),
  	}
  }
docs: // NewAssertContext returns an AssertContext with all fields
  // which can be generated filled in.