Locate all files matching fiven filename pattern in and below
    supplied root directory.

def locate_files(pattern, root_dir=os.curdir):
    """
    Locate all files matching fiven filename pattern in and below
    supplied root directory.
    """
    for dirpath, dirnames, filenames in os.walk(os.path.abspath(root_dir)):
        for filename in fnmatch.filter(filenames, pattern):
            yield os.path.join(dirpath, filename)