Proper indentation for multiline strings?

What is the proper indentation for Python multiline strings within a function?

    def method():
        string = """line one
line two
line three"""

or

    def method():
        string = """line one
        line two
        line three"""

or something else?

It looks kind of weird to have the string hanging outside the function in the first example.

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The textwrap.dedent function allows one to start with correct indentation in the source, and then strip it from the text before use.

The trade-off, as noted by some others, is that this is an extra function call on the literal; take this into account when deciding where to place these literals in your code.

import textwrap

def frobnicate(param):
    """ Frobnicate the scrognate param.

        The Weebly-Ruckford algorithm is employed to frobnicate
        the scrognate to within an inch of its life.

        """
    prepare_the_comfy_chair(param)
    log_message = textwrap.dedent("""\
            Prepare to frobnicate:
            Here it comes...
                Any moment now.
            And: Frobnicate!""")
    weebly(param, log_message)
    ruckford(param)

The trailing \ in the log message literal is to ensure that line break isn’t in the literal; that way, the literal doesn’t start with a blank line, and instead starts with the next full line.

The return value from textwrap.dedent is the input string with all common leading whitespace indentation removed on each line of the string. So the above log_message value will be:

Prepare to frobnicate:
Here it comes...
    Any moment now.
And: Frobnicate!

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