gnu: Add python-graphviz.

* gnu/packages/graphviz.scm (python-graphviz, python2-graphviz): New
variables.

gnu/packages/graphviz.scm

@@ -2,6 +2,7 @@
 ;;; Copyright © 2013, 2015 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2015 Efraim Flashner <efraim@flashner.co.il>
 ;;; Copyright © 2016 Theodoros Foradis <theodoros@foradis.org>
+;;; Copyright © 2017 Ricardo Wurmus <rekado@elephly.net>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -39,7 +40,7 @@ (define-module (gnu packages graphviz)
   #:use-module (gnu packages compression)
   #:use-module (gnu packages gd)
   #:use-module (gnu packages swig)
-  #:use-module ((guix licenses) #:select (lgpl2.0+ epl1.0 lgpl3+)))
+  #:use-module ((guix licenses) #:prefix license:))
 
 (define-public graphviz
   (package
@@ -106,7 +107,30 @@ (define-public graphviz
 networks.  It has important applications in networking, bioinformatics,
 software engineering, database and web design, machine learning, and in visual
 interfaces for other technical domains.")
-    (license epl1.0)))
+    (license license:epl1.0)))
+
+(define-public python-graphviz
+  (package
+    (name "python-graphviz")
+    (version "0.8")
+    (source (origin
+              (method url-fetch)
+              (uri (pypi-uri "graphviz" version ".zip"))
+              (sha256
+               (base32
+                "0i738qb32w93hraxzjwkvnxmrfwcalhjd14fdbah9f2mk46p5748"))))
+    (build-system python-build-system)
+    (native-inputs
+     `(("unzip" ,unzip)))
+    (home-page "https://github.com/xflr6/graphviz")
+    (synopsis "Simple Python interface for Graphviz")
+    (description
+     "This package provides a simple Python interface for the Graphviz graph
+visualization tool suite.")
+    (license license:expat)))
+
+(define-public python2-graphviz
+  (package-with-python2 python-graphviz))
 
 (define-public gts
   (package
@@ -142,7 +166,7 @@ (define-public gts
     (description
      "Library intended to provide a set of useful functions to deal with
 3D surfaces meshed with interconnected triangles.")
-    (license lgpl2.0+)))
+    (license license:lgpl2.0+)))
 
 (define-public xdot
   (package
@@ -185,4 +209,4 @@ (define-public xdot
 @code{graphviz}’s dot language.  Internally, it uses the xdot output format as
 an intermediate format,and @code{gtk} and @code{cairo} for rendering.  Xdot can
 be used either as a standalone application, or as a python library.")
-    (license lgpl3+)))
+    (license license:lgpl3+)))