fix urlretrieve NameError: import tempfile in 03b_net.ipynb

Author: seemab-yamin

fastcore/net.py

@@ -22,6 +22,7 @@
 from .parallel import *
 
 from functools import wraps
+import tempfile
 import json,urllib,contextlib
 import socket,urllib.request,http,urllib
 from contextlib import contextmanager,ExitStack

nbs/03b_net.ipynb

@@ -22,6 +22,7 @@
     "from fastcore.parallel import *\n",
     "\n",
     "from functools import wraps\n",
+    "import tempfile\n",
     "import json,urllib,contextlib\n",
     "import socket,urllib.request,http,urllib\n",
     "from contextlib import contextmanager,ExitStack\n",