Unbound module Graphics Ocaml on Linux mint

i have read multiple identical problem but answers dont fix it.The OCaml toplevel, version 4.11.0+dev0-2019-10-18opam list

# Packages matching: installed# Name              # Installed # Synopsisbase-bigarray       basebase-threads        basebase-unix           baseconf-libX11         1           Virtual package relying on an Xlib system instalconf-pkg-config     1.1         Virtual package relying on pkg-config installatidune                2.4.0       Fast, portable, and opinionated build systemdune-configurator   2.4.0       Helper library for gathering system configuratiodune-private-libs   2.4.0       Private libraries of Dunegraphics            5.1.0       The OCaml graphics libraryocaml               4.10.0      The OCaml compiler (virtual package)ocaml-base-compiler 4.10.0      Official release 4.10.0ocaml-config        1           OCaml Switch Configuration

opam install graphics[NOTE] Package graphics is already installed (current version is 5.1.0).

ocamlfind query -predicates native -a-format graphics

ocamlfind: Package `graphics' not foundme@2020:~$   /home/ivg/.opam/fresh/lib/ocaml/graphics.cmxabash: /home/ivg/.opam/fresh/lib/ocaml/graphics.cmxa: Aucun fichier ou dossier de ce type

ocamlfind ocamlopt -package graphics

ocamlfind: Package `graphics' not found

ls ocamlc -where/graphics*

ls: impossible d'accéder à'/usr/local/lib/ocaml/graphics*': Aucun fichier ou dossier de ce type

sudo apt install libx11-dev

Lecture des listes de paquets... FaitConstruction de l'arbre des dépendances       Lecture des informations d'état... Faitlibx11-dev est déjà la version la plus récente (2:1.6.4-3ubuntu0.2).0 mis à jour, 0 nouvellement installés, 0 à enlever et 8 non mis à jour.

I dont understand what is wrong, it seems to be installed but it cant use it properly ?

ocamlc graphics.cma test1.ml -o test1

File "test1.ml", line 3, characters 5-13:3 | open Graphics;;         ^^^^^^^^Error: Unbound module Graphics