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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 prt_objdesc(self, prt):
 """Return description of this GoSubDag object."""

        txt = "INITIALIZING GoSubDag: {N:3} sources in {M:3} GOs rcnt({R}). {A} alt GO IDs\n"
        alt2obj = {go:o for go, o in self.go2obj.items() if go != o.id}
        prt.write(txt.format(
            N=len(self.go_sources),
            M=len(self.go2obj),
            R=self.rcntobj is not None,
            A=len(alt2obj)))
        prt.write("             GoSubDag: namedtuple fields: {FLDS}\n".format(
            FLDS=" ".join(self.prt_attr['flds'])))
        prt.write("             GoSubDag: relationships: {RELS}\n".format(RELS=self.relationships))