@type t() :: %SBoM.CycloneDX.V15.Metadata{
  __unknown_fields__: [Protobuf.unknown_field()],
  authors: [SBoM.CycloneDX.V15.OrganizationalContact.t()],
  component: SBoM.CycloneDX.V15.Component.t() | nil,
  licenses: SBoM.CycloneDX.V15.LicenseChoice.t() | nil,
  lifecycles: [SBoM.CycloneDX.V15.Lifecycles.t()],
  manufacture: SBoM.CycloneDX.V15.OrganizationalEntity.t() | nil,
  properties: [SBoM.CycloneDX.V15.Property.t()],
  supplier: SBoM.CycloneDX.V15.OrganizationalEntity.t() | nil,
  timestamp: Google.Protobuf.Timestamp.t() | nil,
  tools: SBoM.CycloneDX.V15.Tool.t() | nil
}