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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 create_nodata_node(self, valid_seg, tags=None):
 """ A simplified version of create_node that creates a node that does not need to read in data. Parameters valid_seg : glue.segment The segment over which to declare the node valid. Usually this would be the duration of the analysis. Returns -------- node : pycbc.workflow.core.Node The instance corresponding to the created node. """

        if tags is None:
            tags = []
        node = Node(self)

        # Set the output file
        # Add the PSD file if needed
        if self.write_psd:
            node.new_output_file_opt(valid_seg, '.txt', '--psd-output',
                                     tags=tags+['PSD_FILE'], store_file=self.retain_files)

        node.new_output_file_opt(valid_seg, '.xml.gz', '--output-file',
                                 store_file=self.retain_files)

        if self.psd_files is not None:
            should_add = False

            # If any of the ifos for this job are in the set
            # of ifos for which a static psd was provided.
            for ifo in self.ifo_list:
                for psd_file in self.psd_files:
                    if ifo in psd_file.ifo_list:
                        should_add = True

            if should_add:
                node.add_input_opt('--psd-file', psd_file)

        return node