Make code work on Python 2.

tools/pip_install.py

@@ -11,6 +11,7 @@
 from __future__ import absolute_import
 from __future__ import print_function
 
+import contextlib
 import os
 import re
 import shutil
@@ -23,6 +24,17 @@ import readlink
 import strip_hashes
 
 
+# Once this code doesn't need to support Python 2, we can simply use
+# tempfile.TemporaryDirectory.
+@contextlib.contextmanager
+def temporary_directory():
+    dirpath = tempfile.mkdtemp()
+    try:
+        yield dirpath
+    finally:
+        shutil.rmtree(dirpath)
+
+
 def find_tools_path():
     return os.path.dirname(readlink.main(__file__))
 
@@ -87,12 +99,7 @@ def main(args):
     tools_path = find_tools_path()
     working_dir = tempfile.mkdtemp()
 
-    if os.environ.get('TRAVIS'):
-        # When this script is executed on Travis, the following print will make the log
-        # be folded until the end command is printed (see finally section).
-        print('travis_fold:start:install_certbot_deps')
-
-    try:
+    with temporary_directory() as working_dir:
         test_constraints = os.path.join(working_dir, 'test_constraints.txt')
         all_constraints = os.path.join(working_dir, 'all_constraints.txt')
 
@@ -121,10 +128,6 @@ def main(args):
 
             pip_install_with_print('--constraint "{0}" {1}'.format(
                 all_constraints, ' '.join(args)))
-    finally:
-        if os.environ.get('TRAVIS'):
-            print('travis_fold:end:install_certbot_deps')
-        shutil.rmtree(working_dir)
 
 
 if __name__ == '__main__':

tools/pipstrap.py

@@ -8,6 +8,7 @@ pinned the same way as our other packages.
 from __future__ import absolute_import
 
 import os
+import shutil
 import tempfile
 
 import pip_install
@@ -30,7 +31,7 @@ wheel==0.35.1 \
 
 
 def main():
-    with tempfile.TemporaryDirectory() as tempdir:
+    with pip_install.temporary_directory() as tempdir:
         requirements_filepath = os.path.join(tempdir, 'reqs.txt')
         with open(requirements_filepath, 'w') as f:
             f.write(REQUIREMENTS)