All contents on a line following a `#` are ignored by Python.

This means that in terms of output,

print("one") # print("one")

print("one")
# print("two")

# print("one")
print("one") # hello world
# some more random characters

are all identical (you can check yourself by running all those snippets in Python).

The reason that this is a feature is so that you can add annotations to your programs.