Construct from an h5py.File and a country code.

        Parameters
        ----------
        h5_file : h5py.File
            An HDF5 daily pricing file.
        country_code : str
            The ISO 3166 alpha-2 country code for the country to read.

def from_file(cls, h5_file, country_code):
        """
        Construct from an h5py.File and a country code.

        Parameters
        ----------
        h5_file : h5py.File
            An HDF5 daily pricing file.
        country_code : str
            The ISO 3166 alpha-2 country code for the country to read.
        """
        if h5_file.attrs['version'] != VERSION:
            raise ValueError(
                'mismatched version: file is of version %s, expected %s' % (
                    h5_file.attrs['version'],
                    VERSION,
                ),
            )

        return cls(h5_file[country_code])