Change the string concatenation and formatting to correct python style

Author: Zhen

neo4j/addressing.py

@@ -90,11 +90,11 @@ def parse_routing_context(cls, uri):
         for keyValue in parameters:
             pair = keyValue.split('=')
             if len(pair) != 2 or not pair[0] or not pair[1]:
-                raise ValueError("Invalid parameters: '" + keyValue + "' in URI '" + uri + "'.")
+                raise ValueError("Invalid parameters: '%s' in URI '%s'." % (keyValue, uri))
             key = pair[0]
             value = pair[1]
             if key in context:
-                raise ValueError("Duplicated query parameters with key '" + key + "' found in URL '" + uri + "'")
+                raise ValueError("Duplicated query parameters with key '%s' found in URL '%s'" % (key, uri))
             context[key] = value
         return context
 

neo4j/v1/direct.py

@@ -57,7 +57,7 @@ def __init__(self, uri, **config):
         # the connection pool may contain multiple IP address keys, one for
         # an old address and one for a new address.
         if SocketAddress.parse_routing_context(uri):
-            raise ValueError("Routing parameters are not supported with scheme 'bolt'. Given URI: '" + uri + "'.")
+            raise ValueError("Routing parameters are not supported with scheme 'bolt'. Given URI: '%s'." % uri)
         self.address = SocketAddress.from_uri(uri, DEFAULT_PORT)
         self.security_plan = security_plan = SecurityPlan.build(**config)
         self.encrypted = security_plan.encrypted

neo4j/v1/routing.py

@@ -156,7 +156,7 @@ class RoutingConnectionPool(ConnectionPool):
 
     call_get_servers = "CALL dbms.cluster.routing.getServers"
     get_routing_table_param = "context"
-    call_get_routing_table = "CALL dbms.cluster.routing.getRoutingTable({" + get_routing_table_param + "})"
+    call_get_routing_table = "CALL dbms.cluster.routing.getRoutingTable({%s})" % get_routing_table_param
 
     def __init__(self, connector, initial_address, routing_context, *routers):
         super(RoutingConnectionPool, self).__init__(connector)
@@ -170,7 +170,7 @@ def routing_info_procedure(self, connection):
         if ServerVersion.from_str(connection.server.version).at_least_version(3, 2):
             return self.call_get_routing_table, {self.get_routing_table_param: self.routing_context}
         else:
-            return self.call_get_servers, None
+            return self.call_get_servers
 
     def fetch_routing_info(self, address):
         """ Fetch raw routing info from a given router address.
@@ -315,8 +315,7 @@ def acquire(self, access_mode=None):
                 self.remove(address)
             else:
                 return connection
-        raise SessionExpired("Failed to obtain connection towards '" + access_mode +
-                             "' server. Known routing table is: '" + self.routing_table + "'.")
+        raise SessionExpired("Failed to obtain connection towards '%s' server." % access_mode)
 
     def remove(self, address):
         """ Remove an address from the connection pool, if present, closing