diff --git a/waitredis/__init__.py b/waitredis/__init__.py
index 3846e83..5d0fe90 100644
--- a/waitredis/__init__.py
+++ b/waitredis/__init__.py
@@ -6,14 +6,31 @@
 import redis
 
 
+HOST = 'localhost'
+PORT = 6379
+
+
+def wait_redis(host=HOST, port=PORT, timeout=None):
+    # Connect to redis and wait until it's ready
+    client = redis.StrictRedis(host=host, port=port)
+    start_time = time.time()
+    while timeout is None or time.time() - start_time < timeout:
+        try:
+            client.dbsize()
+        except redis.BusyLoadingError:
+            time.sleep(0.1)
+        else:
+            break
+
+
 def main():
     # Parse command line
     parser = argparse.ArgumentParser(description='Wait until redis has '
             'finished loading the dataset, then run another program',
             formatter_class=argparse.ArgumentDefaultsHelpFormatter)
-    parser.add_argument('--port', '-p', default=6379, type=int, 
+    parser.add_argument('--port', '-p', default=PORT, type=int,
             help='redis port')
-    parser.add_argument('--host', '-H', default='localhost', help='redis host')
+    parser.add_argument('--host', '-H', default=HOST, help='redis host')
     parser.add_argument('--timeout', '-t', help='timeout before giving up; '
             'the default is to wait forever')
     parser.add_argument('command', help='the command to run')
@@ -21,20 +38,7 @@ def main():
             help='the command arguments')
     options = parser.parse_args()
 
-    # Connect to redis and wait until it's ready
-    client = redis.StrictRedis(host=options.host, port=options.port)
-    start_time = time.time()
-    while (options.timeout is None or 
-            time.time() - start_time < options.timeout):
-        try:
-            client.dbsize()
-        except redis.ResponseError as exc:
-            if exc.args[0].startswith('LOADING'):
-                time.sleep(0.1)
-            else:
-                raise
-        else:
-            break
+    wait_redis(options.host, options.port, options.timeout)
 
     # Start command, replacing the current process
     args = [options.command] + options.args