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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _fetch_losc_data_file(url, *args, **kwargs):
 """Internal function for fetching a single LOSC file and returning a Series """

    cls = kwargs.pop('cls', TimeSeries)
    cache = kwargs.pop('cache', None)
    verbose = kwargs.pop('verbose', False)

    # match file format
    if url.endswith('.gz'):
        ext = os.path.splitext(url[:-3])[-1]
    else:
        ext = os.path.splitext(url)[-1]
    if ext == '.hdf5':
        kwargs.setdefault('format', 'hdf5.losc')
    elif ext == '.txt':
        kwargs.setdefault('format', 'ascii.losc')
    elif ext == '.gwf':
        kwargs.setdefault('format', 'gwf')

    with _download_file(url, cache, verbose=verbose) as rem:
        # get channel for GWF if not given
        if ext == ".gwf" and (not args or args[0] is None):
            args = (_gwf_channel(rem, cls, kwargs.get("verbose")),)
        if verbose:
            print('Reading data...', end=' ')
        try:
            series = cls.read(rem, *args, **kwargs)
        except Exception as exc:
            if verbose:
                print('')
            exc.args = ("Failed to read LOSC data from %r: %s"
                        % (url, str(exc)),)
            raise
        else:
            # parse bits from unit in GWF
            if ext == '.gwf' and isinstance(series, StateVector):
                try:
                    bits = {}
                    for bit in str(series.unit).split():
                        a, b = bit.split(':', 1)
                        bits[int(a)] = b
                    series.bits = bits
                    series.override_unit('')
                except (TypeError, ValueError):  # don't care, bad LOSC
                    pass

            if verbose:
                print('[Done]')
            return series