Return a variable vs return a function call

Question

What is the recommended Pythonic way for returning values from a method and why? Is there any documentation on this in the PEP8 style guide, I couldn't find any.

Method 1

def method():
    a = meth2()
    return a

Method 2

def method():
    return meth2()

Answer 1

Method 2 seems good because there isn't any need of a variable if you are just returning the value received from the function. Plus, it looks good this way :P

Method 1 can be used for debug purposes or something else needs to be done before returning the value

Answer 2

Normally I plump for Method 1, particularly in mathematical code.

Method 1 is easier to debug and therefore maintain, since you can put a breakpoint on return a, and see easily what a is. (Wonderful as they are, the C++ Boost programmers like to adopt Method 2 with very large call stacks which can make debugging very difficult - you have to resort to inspecting a CPU register!)

Good python interpreters will have named return value optimisation, so you ought not worry about an unnecessary value copy being taken.