--- a/day1/session3.tex	Fri Oct 23 11:57:16 2009 +0530
+++ b/day1/session3.tex	Fri Oct 23 12:10:27 2009 +0530
@@ -158,8 +158,8 @@
 In []: L = []
 In []: T = []
 In []: for line in open('pendulum.txt'):
-  ....     len, t = line.split()
-  ....     L.append(float(len))
+  ....     ln, t = line.split()
+  ....     L.append(float(ln))
   ....     T.append(float(t))
 \end{lstlisting}
 We now have two lists L and T