def _normalize_docstring(docstring):
if not docstring:<EOL><INDENT>return '<STR_LIT>'<EOL><DEDENT>lines = docstring.expandtabs().splitlines()<EOL>indent = sys.maxsize<EOL>for line in lines[<NUM_LIT:1>:]:<EOL><INDENT>stripped = line.lstrip()<EOL>if stripped:<EOL><INDENT>indent = min(indent, len(line) - len(stripped))<EOL><DEDENT><DEDENT>trimmed = [lines[<NUM_LIT:0>].strip()]<EOL>if indent < sys.maxsize:<EOL><INDENT>for line in lines[<NUM_LIT:1>:]:<EOL><INDENT>trimmed.append(line[indent:].rstrip())<EOL><DEDENT><DEDENT>while trimmed and not trimmed[-<NUM_LIT:1>]:<EOL><INDENT>trimmed.pop()<EOL><DEDENT>while trimmed and not trimmed[<NUM_LIT:0>]:<EOL><INDENT>trimmed.pop(<NUM_LIT:0>)<EOL><DEDENT>return '<STR_LIT:\n>'.join(trimmed)<EOL>
Normalizes the docstring.

    Replaces tabs with spaces, removes leading and trailing blanks lines, and
    removes any indentation.

    Copied from PEP-257:
    https://www.python.org/dev/peps/pep-0257/#handling-docstring-indentation

    Args:
        docstring: the docstring to normalize

    Returns:
        The normalized docstring