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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 update_timegrids(self) -> None: """Update the |Timegrids| object available in module |pub| with the values defined in the `timegrid` XML element. Usually, one would prefer to define `firstdate`, `lastdate`, and `stepsize` elements as in the XML configuration file of the `LahnH` example project: Timegrids(Timegrid('1996-01-01T00:00:00', '1996-01-06T00:00:00', '1d')) Alternatively, one can provide the file path to a `seriesfile`, which must be a valid NetCDF file. The |XMLInterface| object then interprets the file's time information: Timegrids(Timegrid('1996-01-01 00:00:00', '2007-01-01 00:00:00', '1d')) """

        timegrid_xml = self.find('timegrid')
        try:
            timegrid = timetools.Timegrid(
                *(timegrid_xml[idx].text for idx in range(3)))
            hydpy.pub.timegrids = timetools.Timegrids(timegrid)
        except IndexError:
            seriesfile = find(timegrid_xml, 'seriesfile').text
            with netcdf4.Dataset(seriesfile) as ncfile:
                hydpy.pub.timegrids = timetools.Timegrids(
                    netcdftools.query_timegrid(ncfile))