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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 write(self) -> None: """Call method |NetCDFFile.write| of all handled |NetCDFFile| objects. """

        if self.folders:
            init = hydpy.pub.timegrids.init
            timeunits = init.firstdate.to_cfunits('hours')
            timepoints = init.to_timepoints('hours')
            for folder in self.folders.values():
                for file_ in folder.values():
                    file_.write(timeunits, timepoints)