code: func (md *MobileDetect) VersionFloat(propertyName interface{}) float64 {
  	switch propertyName.(type) {
  	case string:
  		return md.properties.versionFloatName(propertyName.(string), md.userAgent)
  	case int:
  		return md.VersionFloatKey(propertyName.(int))
  	}
  	return 0.0
  }
docs: // It is recommended to use VersionFloatKey instead