High level import function that tries to determine the specific version
    of the data format used.

    Parameters
    ----------
    filename: string
        File path to a .mat matlab filename, as produced by the various
        versions of the emmt_pp.exe postprocessing program.

    Returns
    -------
    version: string
        a sanitized version of the file format version

def _get_file_version(filename):
    """High level import function that tries to determine the specific version
    of the data format used.

    Parameters
    ----------
    filename: string
        File path to a .mat matlab filename, as produced by the various
        versions of the emmt_pp.exe postprocessing program.

    Returns
    -------
    version: string
        a sanitized version of the file format version

    """
    mat = sio.loadmat(filename, squeeze_me=True)
    version = mat['MP']['Version'].item()
    del(mat)

    return version