label ladder leap year len with string with list lexicographic ordering library definition of graphicssee graphics library mathsee math library randomsee random library lightning line line continuation using backslash (\) using brackets linear time list as sequence creation empty indexing merging methods operators removing items slice vs string lists decorated literal float int string log time long int loop accumulator variable as control structure counted definite end-of-file event loop for statement indefinite (conditional) index variable infinite interactive loop and half nested over sequence post-test using break using while pre-test while statement loop and half loopfib looppower lower lucasedouard machine code machine language maintenance makestudent mapping math domain error math library functions using max max-of- program max-of-three - maxn py mean median memory main secondary merge merge sort mergesort analysis message encoding algorithm message decoding algorithm problem description program message encoding problem description program meta-language method