diff --git a/test/test.py b/test/test.py
index 0258c3a..1399995 100644
--- a/test/test.py
+++ b/test/test.py
@@ -46,9 +46,22 @@ def fetch_url(src, dst):
 
 
 def exe(command):
+    """
+    Executes command and returns string representations of stdout and stderr captured from the console.
+    When universal_newlines=True stdout and stderr are opened in text mode.
+    Otherwise, they are opened in binary mode. In that case captured stdout and stderr
+    are not strings and Python 3 throws type error when compared against strings later in tests.
+ 
+    Note:
+    This feature is only available if Python is built with universal newline support (the default).
+    Also, the newlines attribute of the file objects stdout, stdin and stderr are not updated by the
+    communicate() method.
+    See https://docs.python.org/2/library/subprocess.html
+    """
     stdout, stderr = subprocess.Popen(shlex.split(command),
                                       stdout=subprocess.PIPE,
-                                      stderr=subprocess.PIPE).communicate()
+                                      stderr=subprocess.PIPE,
+                                      universal_newlines=True).communicate()
     return stdout, stderr
 
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