The code snippet passed into the timeit module are usually passed in as either a string or as a function.

Command-line:

python -m timeit 'print("Hello World")'

Python Interface:

>>> import timeit
>>> timeit.timeit('print("Hello World")')

Inside of a .py file:

import timeit
print(timeit.timeit('print("Hello World")'))

or

import timeit 

def f():
    print("Hello World")

print(timeit.timeit(stmt=f))