def letters_between(text, strl, strr):
    mid = ''
    out = []
    left = None
    for ii, letter in enumerate(text):
        if letter == strl:
            left = ii
            # second to last letter
            if (left == len(text)-2) or (left == len(text)-3):
                mid = text[left+1:]
                out.append((mid, left, len(text)-1))
                left = None
        if left is not None and letter == strr:
            mid = text[left+1: ii]
            out.append((mid, left, ii))
            left = None
    return out
Retrieves the VSS volume object.
dataset/ETHPy150Open xraypy/xraylarch/plugins/xsw/multilayer_film.py/letters_between--crossover with--dataset/ETHPy150Open log2timeline/dfvfs/dfvfs/vfs/vshadow_file_system.py/VShadowFileSystem.GetVShadowVolume