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Complete this python program:
def get_auto_format_func(col_name=None, possible_string_format_functions=_possible_string_format_functions):
assistant
#Here is the Python code you requested.

    """Return a wrapped ``auto_format_func`` function which is used in
    formatting table columns.  This is primarily an internal function but
    gets used directly in other parts of astropy, e.g. `astropy.io.ascii`.
    Parameters
    col_name : object, optional
    Hashable object to identify column like id or name. Default is None.
    possible_string_format_functions : func, optional
    Function that yields possible string formatting functions
    (defaults to internal function to do this).
    Returns
    Wrapped ``auto_format_func`` function
    """
    def _auto_format_func(format_, val):
        u'Format    ``val``    according    to    ``format_``    for    a    plain    format    specifier,\n                                old-    or    new-style    format    strings,    or    using    a    user    supplied    function.\n                                More    importantly,    determine    and    cache    (in    _format_funcs)    a    function\n                                that    will    do    this    subsequently.        In    this    way    this    complicated    logic    is\n                                only    done    for    the    first    value.\n\n                                Returns    the    formatted    value.\n                                '
        if (format_ is None):
            return default_format_func(format_, val)
        format_key = (format_, col_name)
        if (format_key in _format_funcs):
            return _format_funcs[format_key](format_, val)
        if six.callable(format_):
            format_func = (lambda format_, val: format_(val))
            try:
                out = format_func(format_, val)
                if (not isinstance(out, six.string_types)):
                    raise ValueError(u'Format    function    for    value    {0}    returned    {1}    instead    of    string    type'.format(val, type(val)))
            except Exception as err:
                if (val is np.ma.masked):
                    return str(val)
                raise ValueError(u'Format    function    for    value    {0}    failed:    {1}'.format(val, err))
            try:
                format_func(format_, np.ma.masked)
            except Exception:
                format_func = _use_str_for_masked_values(format_func)
        else:
            if (val is np.ma.masked):
                return str(val)
            for format_func in possible_string_format_functions(format_):
                try:
                    out = format_func(format_, val)
                    if (out == format_):
                        raise...