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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 _from_yang_library(self, yang_lib: Dict[str, Any]) -> None: """Set the schema structures from YANG library data. Args: yang_lib: Dictionary with YANG library data. Raises: BadYangLibraryData: If YANG library data is invalid. FeaturePrerequisiteError: If a pre-requisite feature isn't supported. MultipleImplementedRevisions: If multiple revisions of an implemented module are listed in YANG library. ModuleNotFound: If a YANG module wasn't found in any of the directories specified in `mod_path`. """

        try:
            for item in yang_lib["ietf-yang-library:modules-state"]["module"]:
                name = item["name"]
                rev = item["revision"]
                mid = (name, rev)
                mdata = ModuleData(mid)
                self.modules[mid] = mdata
                if item["conformance-type"] == "implement":
                    if name in self.implement:
                        raise MultipleImplementedRevisions(name)
                    self.implement[name] = rev
                mod = self._load_module(name, rev)
                mdata.statement = mod
                if "feature" in item:
                    mdata.features.update(item["feature"])
                locpref = mod.find1("prefix", required=True).argument
                mdata.prefix_map[locpref] = mid
                if "submodule" in item:
                    for s in item["submodule"]:
                        sname = s["name"]
                        smid = (sname, s["revision"])
                        sdata = ModuleData(mid)
                        self.modules[smid] = sdata
                        mdata.submodules.add(smid)
                        submod = self._load_module(*smid)
                        sdata.statement = submod
                        bt = submod.find1("belongs-to", name, required=True)
                        locpref = bt.find1("prefix", required=True).argument
                        sdata.prefix_map[locpref] = mid
        except KeyError as e:
            raise BadYangLibraryData("missing " + str(e)) from None
        self._process_imports()
        self._check_feature_dependences()