Some(Signature(
            typeParams = Seq(Type("classConv.T", constraints = ": Writer")),
            parameterLists = Seq(
              DeclaredParameterList(
                isImplicit = false,
                params = DeclaredParameter()
              )
            )
            returnType = Type("classConv.Hello", parameters = Seq(Type("classConv.T")))
          ))