diff --git a/check50.py b/check50.py
index 0927033c..0a187bef 100755
--- a/check50.py
+++ b/check50.py
@@ -248,7 +248,7 @@ def print_json(results):
             pass
 
         output.append(obj)
-    print(json.dumps(output))
+    print(json.dumps(output, cls=Encoder))
 
 
 def import_checks(identifier):
@@ -426,6 +426,15 @@ def wrapper(self):
     return decorator
 
 
+class Encoder(json.JSONEncoder):
+    """Custom class for JSON encoding."""
+
+    def default(self, o):
+        if o == EOF:
+            return "EOF"
+        return o.__dict__
+
+
 class File(object):
     """Generic class to represent file in check directory."""
 
diff --git a/setup.py b/setup.py
index 2b1ac814..f6845cd7 100644
--- a/setup.py
+++ b/setup.py
@@ -60,5 +60,5 @@ class CustomInstall(install):
         "console_scripts": ["check50=check50:main"]
     },
     url="https://github.com/cs50/check50",
-    version="2.1.2"
+    version="2.1.3"
 )