diff --git a/ipynb/BASIC.ipynb b/ipynb/BASIC.ipynb
index b711164..3569717 100644
--- a/ipynb/BASIC.ipynb
+++ b/ipynb/BASIC.ipynb
@@ -201,10 +201,6 @@
     "    top = peek()\n",
     "    if constraint is None or (top == constraint) or (callable(constraint) and constraint(top)):\n",
     "        return tokens.pop(0)\n",
-    "    \n",
-    "def remove_spaces(line): \n",
-    "    \"Remove white space from line, except space inside double quotes.\"\n",
-    "    return \n",
     "\n",
     "def lines(text): \n",
     "    \"A list of the non-empty lines in a text.\"\n",