matplotlib
diff --git a/‎INSTALL
Copy file name to clipboardExpand all lines: INSTALL
+1-1Lines changed: 1 addition & 1 deletion b/‎INSTALL
Copy file name to clipboardExpand all lines: INSTALL
+1-1Lines changed: 1 addition & 1 deletion
diff --git a/‎setupext.py
Copy file name to clipboardExpand all lines: setupext.py
+3Lines changed: 3 additions & 0 deletions b/‎setupext.py
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+3Lines changed: 3 additions & 0 deletions
@@ -319,4 +319,4 @@ Framework with Visual Studio).  In addition to Visual Studio `CMake
 
 Since there is no canonical Windows package manager the build methods for
 freetype, zlib, libpng, tcl, & tk source code are documented as a build script
-at `matplotlib-winbuild <https://github.com/jbmohler/matplotlib-winbuild>`.
+at `matplotlib-winbuild <https://github.com/jbmohler/matplotlib-winbuild>`_.
@@ -1003,6 +1003,9 @@ class Png(SetupPackage):
     name = "png"
 
     def check(self):
+        if sys.platform == 'win32':
+            return "Unknown version"
+
         status, output = getstatusoutput("libpng-config --version")
         if status == 0:
             version = output