Is there a way to use a variable in a single string value accompanied with text?

There are two other methods that I would recommend. The first of which is concatenation which is accomplished via the '+' character. Here is how it would look in your code:

print("Hello, "  + label_tag),

you can concatenate as many strings together as you'd like in one line! Here's an example:

my_number = 4
print("My number is: " + str(my_number) + ". What's yours?")

Your output would be:

My number is: 4. What's yours?

Another method which is less pretty but much more efficient is to use the .'format'. Here is an example:

my_number = 4
print("My number is: {}. What's yours?".format(my_number))

This will output the same thing as before. The way that format works is it replaces the '{}' in your string with the variable that you input. Note that the inputted variable does not have to be a string as format will convert it for you. if you want to add multiple format elements you can simply add more '{}' into your string:

my_number = 4
your_number = 7
print("My number is: {}. Your number is {}.".format(my_number, your_number))

This will output:

My number is: 4. Your number is 7.

As you can see it will just replace the '{}' elements from left to right. There is also a lot more functionality that I'm not going to get into with this method, but you can feel free to check it out here: https://docs.python.org/3.4/library/string.html