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How to Write Comments in Python
let’s go over some basics so you know how to write comments properly in python.

Python Commenting Basics
Comments are for developers. They describe parts of the code where necessary to facilitate the understanding of programmers, including yourself.

To write a comment in Python, simply put the hash mark # before your desired comment:

# This is a comment
Python ignores everything after the hash mark and up to the end of the line. You can insert them anywhere in your code, even inline with other code:

print("This will run.") # This won't run
When you run the above code, you will only see the output This will run. Everything else is ignored.

Comments should be short, sweet, and to the point. While PEP 8 advises keeping code at 79 characters or fewer per line, it suggests a max of 72 characters for inline comments and docstrings. If your comment is approaching or exceeding that length, then you’ll want to spread it out over multiple lines.

Python Multiline Comments
Unfortunately, Python doesn’t have a way to write multiline comments as you can in languages such as C, Java, and Go:

# So you can't
just do this
in python
In the above example, the first line will be ignored by the program, but the other lines will raise a Syntax Error.

In contrast, a language like Java will allow you to spread a comment out over multiple lines quite easily:

/* You can easily
write multiline
comments in Java */
Everything between /* and */ is ignored by the program.

While Python doesn’t have native multiline commenting functionality, you can create multiline comments in Python. There are two simple ways to do so.

The first way is simply by pressing the return key after each line, adding a new hash mark and continuing your comment from there:

def multiline_example():
# This is a pretty good example
# of how you can spread comments
# over multiple lines in Python
Each line that starts with a hash mark will be ignored by the program.

Another thing you can do is use multiline strings by wrapping your comment inside a set of triple quotes:

"""
If I really hate pressing `enter` and
typing all those hash marks, I could
just do this instead
"""
This is like multiline comments in Java, where everything enclosed in the triple quotes will function as a comment.

While this gives you the multiline functionality, this isn’t technically a comment. It’s a string that’s not assigned to any variable, so it’s not called or referenced by your program. Still, since it’ll be ignored at runtime and won’t appear in the bytecode, it can effectively act as a comment. (You can take a look at this article for proof that these strings won’t show up in the bytecode.)

However, be careful where you place these multiline “comments.” Depending on where they sit in your program, they could turn into docstrings, which are pieces of documentation that are associated with a function or method. If you slip one of these bad boys right after a function definition, then what you intended to be a comment will become associated with that object.

Be careful where you use these, and when in doubt, just put a hash mark on each subsequent line. If you’re interested in learning more about docstrings and how to associate them with modules, classes, and the like, check out our tutorial on Documenting Python Code.

Python Commenting Shortcuts
It can be tedious to type out all those hash marks every time you need to add a comment. So what can you do to speed things up a bit? Here are a few tricks to help you out when commenting.

One of the first things you can do is use multiple cursors. That’s exactly what it sounds like: placing more than one cursor on your screen to accomplish a task. Simply hold down the Ctrl or Cmd key while you left-click, and you should see the blinking lines on your screen:

Python Comments Multiple Cursors
This is most effective when you need to comment the same thing in several places.

What if you’ve got a long stretch of text that needs to be commented out? Say you don’t want a defined function to run in order to check for a bug. Clicking each and every line to comment it out could take a lot of time! In these cases, you’ll want to toggle comments instead. Simply select the desired code and press Ctrl+/ on PC, or Cmd+/ on Mac:

Python Toggle Comments
All the highlighted text will be prepended with a hash mark and ignored by the program.
If your comments are getting too unwieldy, or the comments in a script you’re reading are really long, then your text editor may give you the option to collapse them using the small down arrow on the left-hand side:
Python Hide Comments
Simply click the arrow to hide the comments. This works best with long comments spread out over multiple lines, or docstrings that take up most of the start of a program.

Combining these tips will make commenting on your code quick, easy, and painless!

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