code: func (c *Callbacks) OnCDOTAMatchMetadataFile(fn func(*dota.CDOTAMatchMetadataFile) error) {
  	c.onCDOTAMatchMetadataFile = append(c.onCDOTAMatchMetadataFile, fn)
  }
docs: // OnCDOTAMatchMetadataFile registers a callback for EDotaUserMessages_DOTA_UM_MatchMetadata