generate a new pyemu.Pst instance from model interface files.  This
    function is emulated in the Pst.from_io_files() class method.

    Parameters
    ----------
    tpl_files : (list)
        template file names
    in_files : (list)
        model input file names
    ins_files : (list)
        instruction file names
    out_files : (list)
        model output file names
    pst_filename : str
        filename to save new pyemu.Pst.  If None, Pst is not written.
        default is None

    Returns
    -------
    new_pst : pyemu.Pst

def pst_from_io_files(tpl_files,in_files,ins_files,out_files,pst_filename=None):
    """ generate a new pyemu.Pst instance from model interface files.  This
    function is emulated in the Pst.from_io_files() class method.

    Parameters
    ----------
    tpl_files : (list)
        template file names
    in_files : (list)
        model input file names
    ins_files : (list)
        instruction file names
    out_files : (list)
        model output file names
    pst_filename : str
        filename to save new pyemu.Pst.  If None, Pst is not written.
        default is None

    Returns
    -------
    new_pst : pyemu.Pst

    """

    warnings.warn("pst_from_io_files has moved to pyemu.helpers and is also "+\
                  "now avaiable as a Pst class method (Pst.from_io_files())",PyemuWarning)
    from pyemu import helpers
    return helpers.pst_from_io_files(tpl_files=tpl_files,in_files=in_files,
                              ins_files=ins_files,out_files=out_files,
                              pst_filename=pst_filename)