diff --git a/integrations/basecamp/zulip_basecamp_mirror b/integrations/basecamp/zulip_basecamp_mirror
index 92b0ed4..8bdf2f4 100755
--- a/integrations/basecamp/zulip_basecamp_mirror
+++ b/integrations/basecamp/zulip_basecamp_mirror
@@ -84,7 +84,7 @@ def check_permissions():
 def build_message(event):
     if not ('bucket' in event and 'creator' in event and 'html_url' in event):
         logging.error("Perhaps the Basecamp API changed behavior? "
-                      "This event doesn't have the expected format:\n%s" %(event,))
+                      "This event doesn't have the expected format:\n%s" % (event,))
         return None
     # adjust the topic length to be bounded to 60 characters
     topic = event['bucket']['name']
diff --git a/zulip/__init__.py b/zulip/__init__.py
index bacfcf1..ff726b8 100644
--- a/zulip/__init__.py
+++ b/zulip/__init__.py
@@ -230,28 +230,28 @@ class Client(object):
         self.client_name = client
 
         if insecure:
-            self.tls_verification=False
+            self.tls_verification = False
         elif cert_bundle is not None:
             if not os.path.isfile(cert_bundle):
                 raise RuntimeError("tls bundle '%s' does not exist"
-                                   %(cert_bundle,))
-            self.tls_verification=cert_bundle
+                                   % (cert_bundle,))
+            self.tls_verification = cert_bundle
         else:
             # Default behavior: verify against system CA certificates
-            self.tls_verification=True
+            self.tls_verification = True
 
         if client_cert is None:
             if client_cert_key is not None:
                 raise RuntimeError("client cert key '%s' specified, but no client cert public part provided"
-                                   %(client_cert_key,))
+                                   % (client_cert_key,))
         else: # we have a client cert
             if not os.path.isfile(client_cert):
                 raise RuntimeError("client cert '%s' does not exist"
-                                   %(client_cert,))
+                                   % (client_cert,))
             if client_cert_key is not None:
                 if not os.path.isfile(client_cert_key):
                     raise RuntimeError("client cert key '%s' does not exist"
-                                       %(client_cert_key,))
+                                       % (client_cert_key,))
         self.client_cert = client_cert
         self.client_cert_key = client_cert_key