very basic python question

can some one please give me the most basic explanation for the following:

Variables
Strings
White Space

Also, Im learning off the book "python crash course" by eric matthes, (great book so far) any way trying to use concatenation to compose a message and the store that message in a variable the book says my line of code should look like the following:

message = "Hello, " + full_name.title() + "!"
print(message)
I keep getting invalid syntax for the "!"

I know this is so very basic, and i was going to skip right over it, till i ran into the problem again but i felt like i might as well, figure out what im doing wrong before moving on. Thanks for the help

#noob

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