From 6fcab4db132cbc504d8a06dd3ecc0466a9c47356 Mon Sep 17 00:00:00 2001
From: Antony Lee <anntzer.lee@gmail.com>
Date: Thu, 22 Mar 2018 19:39:15 -0700
Subject: [PATCH] Backport PR #10867: MNT: move bz2 back to function level

---
 lib/matplotlib/cbook/__init__.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/matplotlib/cbook/__init__.py b/lib/matplotlib/cbook/__init__.py
index 093404566e32..578ebf9b2bf7 100644
--- a/lib/matplotlib/cbook/__init__.py
+++ b/lib/matplotlib/cbook/__init__.py
@@ -10,7 +10,6 @@
 
 import six
 from six.moves import xrange, zip
-import bz2
 import collections
 import contextlib
 import datetime
@@ -602,6 +601,9 @@ def to_filehandle(fname, flag='rU', return_opened=False, encoding=None):
             flag = flag.replace('U', '')
             fh = gzip.open(fname, flag)
         elif fname.endswith('.bz2'):
+            # python may not be complied with bz2 support,
+            # bury import until we need it
+            import bz2
             # get rid of 'U' in flag for bz2 files
             flag = flag.replace('U', '')
             fh = bz2.BZ2File(fname, flag)