diff --git a/debian/changelog b/debian/changelog
index 0d7c960..c52429a 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,9 +1,9 @@
-ctdconverter (2.0-3) UNRELEASED; urgency=medium
+ctdconverter (2.0-3) unstable; urgency=medium
 
   * Add missing build-dep on 2to3
   * Quiet 2to3 conversion
 
- -- Michael R. Crusoe <michael.crusoe@gmail.com>  Thu, 22 Feb 2018 02:08:21 -0800
+ -- Michael R. Crusoe <michael.crusoe@gmail.com>  Thu, 22 Feb 2018 08:19:00 -0800
 
 ctdconverter (2.0-2) unstable; urgency=medium
 
diff --git a/debian/patches/py3_compat b/debian/patches/py3_compat
new file mode 100644
index 0000000..65ba38a
--- /dev/null
+++ b/debian/patches/py3_compat
@@ -0,0 +1,22 @@
+From: Michael R. Crusoe <michael.crusoe@gmail.com>
+Subject: use `open` instead of `file`
+--- ctdconverter.orig/cwl/converter.py
++++ ctdconverter/cwl/converter.py
+@@ -72,7 +72,7 @@
+ 
+         logger.info("Writing to %s" % utils.get_filename(output_file), 1)
+ 
+-        stream = file(output_file, 'w')
++        stream = open(output_file, 'w')
+         stream.write(CWL_SHEBANG + '\n\n')
+         stream.write("# This CWL file was automatically generated using CTDConverter.\n")
+         stream.write("# Visit https://github.com/WorkflowConversion/CTDConverter for more information.\n\n")
+@@ -103,6 +103,8 @@
+         param_name = utils.extract_param_name(param)
+         cwl_fixed_param_name = fix_param_name(param_name)
+         hardcoded_value = args.parameter_hardcoder.get_hardcoded_value(param_name, ctd_model.name)
++        if isinstance(param.default, map):
++            param.default = list(param.default)
+         param_default = str(param.default) if param.default is not _Null and param.default is not None else None
+ 
+         if param.type is _OutFile:
diff --git a/debian/patches/series b/debian/patches/series
index 94f50c9..0ec2d6a 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -1,3 +1,4 @@
 add_setup.py.patch
 upgrade_deprecated_strip
 correct_name
+py3_compat