nix flake for python opencv playing video file

flake.nix

{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    flake-utils.url = "github:numtide/flake-utils";
  };
  outputs = {
    self,
    nixpkgs,
    flake-utils,
  }:
    flake-utils.lib.eachDefaultSystem (
      system:
      let
        pkgs = import nixpkgs { inherit system; };
      in
        with pkgs; {
          devShells.default = mkShell {
            buildInputs = [ (python311Packages.opencv4.override { enableGtk2 = true; }) ];
          };
        }
    );
}