def get_or_guess_paths_to_mutate(paths_to_mutate):
if paths_to_mutate is None:<EOL><INDENT>this_dir = os.getcwd().split(os.sep)[-<NUM_LIT:1>]<EOL>if isdir('<STR_LIT>'):<EOL><INDENT>return '<STR_LIT>'<EOL><DEDENT>elif isdir('<STR_LIT:src>'):<EOL><INDENT>return '<STR_LIT:src>'<EOL><DEDENT>elif isdir(this_dir):<EOL><INDENT>return this_dir<EOL><DEDENT>elif isdir(this_dir.replace('<STR_LIT:->', '<STR_LIT:_>')):<EOL><INDENT>return this_dir.replace('<STR_LIT:->', '<STR_LIT:_>')<EOL><DEDENT>elif isdir(this_dir.replace('<STR_LIT:U+0020>', '<STR_LIT:_>')):<EOL><INDENT>return this_dir.replace('<STR_LIT:U+0020>', '<STR_LIT:_>')<EOL><DEDENT>elif isdir(this_dir.replace('<STR_LIT:->', '<STR_LIT>')):<EOL><INDENT>return this_dir.replace('<STR_LIT:->', '<STR_LIT>')<EOL><DEDENT>elif isdir(this_dir.replace('<STR_LIT:U+0020>', '<STR_LIT>')):<EOL><INDENT>return this_dir.replace('<STR_LIT:U+0020>', '<STR_LIT>')<EOL><DEDENT>else:<EOL><INDENT>raise FileNotFoundError(<EOL>'<STR_LIT>'<EOL>'<STR_LIT>'<EOL>'<STR_LIT>')<EOL><DEDENT><DEDENT>else:<EOL><INDENT>return paths_to_mutate<EOL><DEDENT>
:type paths_to_mutate: str or None
:rtype: str