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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 get_fout_base(self, goid, name=None, pre="gogrp"):
 """Get filename for a group of GO IDs under a single header GO ID."""

        goobj = self.gosubdag.go2obj[goid]
        if name is None:
            name = self.grpname.replace(" ", "_")
        sections = "_".join(self.hdrobj.get_sections(goid))
        return "{PRE}_{BP}_{NAME}_{SEC}_{DSTR}_{D1s}_{GO}".format(
            PRE=pre,
            BP=Consts.NAMESPACE2NS[goobj.namespace],
            NAME=self._str_replace(name),
            SEC=self._str_replace(self._str_replace(sections)),
            GO=goid.replace(":", ""),
            DSTR=self._get_depthsr(goobj),
            D1s=self.gosubdag.go2nt[goobj.id].D1)