The empty parentheses after the name indicate that this function doesn’t take any arguments.
The first line of the function definition is called the header; the rest is called the body. The
header has to end with a colon and the body has to be indented. By convention, indentation
is always four spaces. The body can contain any number of statements.
The strings in the print statements are enclosed in double quotes. Single quotes and double
quotes do the same thing; most people use single quotes except in cases like this where a
single quote (which is also an apostrophe) appears in the string.
All quotation marks (single and double) must be “straight quotes”, usually located next
to Enter on the keyboard. “Curly quotes”, like the ones in this sentence, are not legal in
Python.
If you type a function definition in interactive mode, the interpreter prints dots (...) to let
you know that the definition isn’t complete: