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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_hdr_childcnt(self, goobj, ntgo):
 """Get string representing count of children for this GO term."""

        if 'childcnt' in self.present:
            return "c{N}".format(N=len(goobj.children))
        elif self.gosubdag.relationships and not goobj.children and ntgo.dcnt != 0:
            return "c0"