default.nix

with import <nixpkgs> {};
let
  ebaysdk = pythonPackages.buildPythonPackage rec {
    name = "ebaysdk-${version}";
    version = "2.1.4";

    src = fetchFromGitHub {
      owner = "timotheus";
      repo = "ebaysdk-python";
      rev = "v${version}";
      sha256 = "03yh601wi05b4cw89rk16l8xmbj2dm58rsrvmsp53k59r08lgdqn";
    };

    propagatedBuildInputs = with pythonPackages; [
      requests
      lxml
    ];

    doCheck = false;
  };
in
  pythonPackages.buildPythonApplication rec {
    name = "your-app-name";
    src = ./.;
    propagatedBuildInputs = with pythonPackages; [
      # list packages here
      ebaysdk
    ];
  }