pythonPackages.pywatchman: move to python-modules

pywatchman is licensed under BSD-3

    https://github.com/facebook/watchman/commit/150f1fb4eff94c0248b54154fb356f768a131d60

pkgs/development/python-modules/pywatchman/default.nix

@@ -0,0 +1,26 @@
+{ stdenv, buildPythonPackage, fetchPypi, watchman }:
+
+buildPythonPackage rec {
+  pname = "pywatchman";
+  version = "1.4.1";
+
+  src = fetchPypi {
+    inherit pname version;
+    sha256 = "1yf2gm20wc3djpb5larxii3l55xxby0il2ns3q0v1byyfnr7w16h";
+  };
+
+  postPatch = ''
+    substituteInPlace pywatchman/__init__.py \
+      --replace "'watchman'" "'${watchman}/bin/watchman'"
+  '';
+
+  # No tests in archive
+  doCheck = false;
+
+  meta = with stdenv.lib; {
+    description = "Watchman client for Python";
+    homepage = https://facebook.github.io/watchman/;
+    license = licenses.bsd3;
+  };
+
+}

pkgs/top-level/python-packages.nix

@@ -4429,21 +4429,7 @@ in {
     };
   };
 
-  pywatchman = buildPythonPackage rec {
+  pywatchman = callPackage ../development/python-modules/pywatchman { };
-    name = "pywatchman-${version}";
-    version = "1.4.1";
-    src = pkgs.fetchurl {
-      url = "mirror://pypi/p/pywatchman/pywatchman-${version}.tar.gz";
-      sha256 = "1yf2gm20wc3djpb5larxii3l55xxby0il2ns3q0v1byyfnr7w16h";
-    };
-    postPatch = ''
-      substituteInPlace pywatchman/__init__.py \
-        --replace "'watchman'" "'${pkgs.watchman}/bin/watchman'"
-    '';
-    # No tests in archive
-    doCheck = false;
-
-  };
 
   pywavelets = callPackage ../development/python-modules/pywavelets { };