diff --git a/package_manager/parse_metadata.py b/package_manager/parse_metadata.py
index 738538b9c..41c3a52ae 100644
--- a/package_manager/parse_metadata.py
+++ b/package_manager/parse_metadata.py
@@ -13,7 +13,7 @@
 # limitations under the License.
 import re
 
-from six import itervalues
+import six
 
 INDEX_KEY = "Package"
 FILENAME_KEY = "Filename"
@@ -22,6 +22,11 @@
 def parse_package_metadata(data, mirror_url, snapshot, package_prefix):
     """ Takes a debian package list, changes the relative urls to absolute urls,
     and saves the resulting metadata as a json file """
+
+    # this is called with the output of gzip.open, but should be strings
+    if isinstance(data, six.binary_type):
+        data = data.decode('utf-8')
+
     raw_entries = [line.rstrip() for line in data.splitlines()]
     parsed_entries = {}
     current_key = None
@@ -55,7 +60,7 @@ def parse_package_metadata(data, mirror_url, snapshot, package_prefix):
     # The Filename Key is a relative url pointing to the .deb package
     # Here, we're rewriting the metadata with the absolute urls,
     # which is a concatenation of the mirror + '/debian/' + relative_path
-    for pkg_data in itervalues(parsed_entries):
+    for pkg_data in six.itervalues(parsed_entries):
         if package_prefix:
             pkg_data[FILENAME_KEY] = package_prefix + pkg_data[FILENAME_KEY]
         else:
diff --git a/package_manager/parse_metadata_test.py b/package_manager/parse_metadata_test.py
index 4f83243fb..7d0a4594e 100644
--- a/package_manager/parse_metadata_test.py
+++ b/package_manager/parse_metadata_test.py
@@ -8,7 +8,8 @@ class TestParseMetadata(unittest.TestCase):
     def setUp(self):
         current_dir = os.path.dirname(__file__)
         filename = os.path.join(current_dir, 'testdata', 'Packages.txt')
-        with open(filename) as f:
+        # parse_package_metadata is called on the binary output of gzip.open
+        with open(filename, 'rb') as f:
             data = f.read()
         self.data = data
         self.mirror_url = "http://debian.org"