fix admin client example

Author: mhowlett

README.md

@@ -177,18 +177,22 @@ c.close()
 Create topics:
 
 ```python
-    new_topics = [NewTopic(topic, num_partitions=3, replication_factor=1) for topic in topics]
-    # Call create_topics to asynchronously create topics, a dict
-    # of <topic,future> is returned.
-    fs = a.create_topics(new_topics)
-
-    # Wait for each operation to finish.
-    for topic, f in fs.items():
-        try:
-            f.result()  # The result itself is None
-            print("Topic {} created".format(topic))
-        except Exception as e:
-            print("Failed to create topic {}: {}".format(topic, e))
+from confluent_kafka.admin import AdminClient, NewTopic
+
+a = AdminClient({'bootstrap.servers': 'mybroker'})
+
+new_topics = [NewTopic(topic, num_partitions=3, replication_factor=1) for topic in ["topic1", "topic2"]]
+# Call create_topics to asynchronously create topics, a dict
+# of <topic,future> is returned.
+fs = a.create_topics(new_topics)
+
+# Wait for each operation to finish.
+for topic, f in fs.items():
+    try:
+        f.result()  # The result itself is None
+        print("Topic {} created".format(topic))
+    except Exception as e:
+        print("Failed to create topic {}: {}".format(topic, e))
 ```