diff --git a/CTFd/__init__.py b/CTFd/__init__.py
index fe88ea55..50f936aa 100644
--- a/CTFd/__init__.py
+++ b/CTFd/__init__.py
@@ -7,7 +7,7 @@ from sqlalchemy.engine.url import make_url
 from sqlalchemy.exc import OperationalError, ProgrammingError
 from sqlalchemy_utils import database_exists, create_database
 
-from utils import get_config, set_config, cache, migrate, migrate_upgrade
+from CTFd.utils import get_config, set_config, cache, migrate, migrate_upgrade
 
 __version__ = '1.0.0'
 
diff --git a/CTFd/config.py b/CTFd/config.py
index 3261e445..e6d6ff0f 100644
--- a/CTFd/config.py
+++ b/CTFd/config.py
@@ -2,7 +2,7 @@ import os
 
 ##### GENERATE SECRET KEY #####
 
-with open('.ctfd_secret_key', 'a+') as secret:
+with open('.ctfd_secret_key', 'a+b') as secret:
     secret.seek(0)  # Seek to beginning of file since a+ mode leaves you at the end and w+ deletes the file
     key = secret.read()
     if not key:
@@ -23,7 +23,7 @@ class Config(object):
 
     http://flask.pocoo.org/docs/0.11/quickstart/#sessions
     '''
-    SECRET_KEY = key
+    SECRET_KEY = os.environ.get('SECRET_KEY') or key
 
 
     '''
diff --git a/CTFd/models.py b/CTFd/models.py
index 440267ae..7248c065 100644
--- a/CTFd/models.py
+++ b/CTFd/models.py
@@ -10,7 +10,7 @@ from sqlalchemy.exc import DatabaseError
 
 
 def sha512(string):
-    return hashlib.sha512(string).hexdigest()
+    return str(hashlib.sha512(string).hexdigest())
 
 
 def ip2long(ip):
diff --git a/CTFd/plugins/__init__.py b/CTFd/plugins/__init__.py
index 1a8a4fbd..39508e89 100644
--- a/CTFd/plugins/__init__.py
+++ b/CTFd/plugins/__init__.py
@@ -5,7 +5,7 @@ import os
 
 def init_plugins(app):
     modules = glob.glob(os.path.dirname(__file__) + "/*")
-    blacklist = {'keys', 'challenges'}
+    blacklist = {'keys', 'challenges', '__pycache__'}
     for module in modules:
         module_name = os.path.basename(module)
         if os.path.isdir(module) and module_name not in blacklist: