2.12 Functions
In this section, we combine many of the techniques in this chapter into examples of functions.
2.12.1 A simple function
This Python code is the definition of an identity function:
def identity(x):
return x
identity takes one parameter
x, does nothing to it, and returns it.
A function definition begins with def followed by the function
name. After that, we list zero or more named parameters in parentheses. We end the line with a
colon. The body of the function starts on the next line and is indented.
Because of the way I wrote identity, it doesn’t care what
the type of x is. It is overloaded to work on anything.
identity(7)
7
identity("just a string")
'just a string'
identity(["one", 2, 3.0])
['one', 2, 3.0]
The definition of identity defined the parameter
x. A parameter...
