diff --git a/IPython/terminal/interactiveshell.py b/IPython/terminal/interactiveshell.py
index ef8cd3f..f1f4444 100644
--- a/IPython/terminal/interactiveshell.py
+++ b/IPython/terminal/interactiveshell.py
@@ -238,7 +238,7 @@ class TerminalInteractiveShell(InteractiveShell):
                             editing_mode=editing_mode,
                             key_bindings_registry=kbmanager.registry,
                             history=history,
-                            completer=IPythonPTCompleter(self.Completer),
+                            completer=IPythonPTCompleter(self),
                             enable_history_search=True,
                             style=style,
                             mouse_support=self.mouse_support,
diff --git a/IPython/terminal/ptutils.py b/IPython/terminal/ptutils.py
index 092373e..1dd4b72 100644
--- a/IPython/terminal/ptutils.py
+++ b/IPython/terminal/ptutils.py
@@ -12,8 +12,12 @@ import pygments.lexers as pygments_lexers
 
 class IPythonPTCompleter(Completer):
     """Adaptor to provide IPython completions to prompt_toolkit"""
-    def __init__(self, ipy_completer):
-        self.ipy_completer = ipy_completer
+    def __init__(self, shell):
+        self.shell = shell
+    
+    @property
+    def ipy_completer(self):
+        return self.shell.Completer
 
     def get_completions(self, document, complete_event):
         if not document.current_line.strip():