How to write comment in python ?

Python Programming 

Comments 

As programs get bigger and more complicated, they get more difficult to read. Formal

languages are dense, and it is often difficult to look at a piece of code and figure out what

it is doing, or why.

For this reason, it is a good idea to add notes to your programs to explain in natural

language what the program is doing. These notes are called comments, and they start with

the # symbol:

    

     #compute the percentage of the hour that has elapsed

    percentage = (minute * 100) / 60 

In this case, the comment appears on a line by itself. You can also put comments at the end

of a line:

                     percentage = (minute * 100) / 60 # percentage of an hour

Everything from the # to the end of the line is ignored — it has no effect on the execution

of the program.

Comments are most useful when they document non-obvious features of the code. It is

reasonable to assume that the reader can figure out what the code does; it is more useful to

explain why.

This comment is redundant with the code and useless:

                          v = 5 # assign 5 to v

This comment contains useful information that is not in the code:

                        v = 5 # velocity in meters/second.

Good variable names can reduce the need for comments, but long names can make

complex expressions hard to read, so there is a trade-off.