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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 load_uri(self, uri):
 """ Load a single resource into the graph for this object. Approach: try loading into a temporary graph first, if that succeeds merge it into the main graph. This allows to deal with the JSONLD loading issues which can solved only by using a ConjunctiveGraph (https://github.com/RDFLib/rdflib/issues/436). Also it deals with the RDFA error message which seems to stick into a graph even if the parse operation fails. NOTE the final merge operation can be improved as graph-set operations involving blank nodes could case collisions (https://rdflib.readthedocs.io/en/stable/merging.html) :param uri: single RDF source location :return: None (sets self.rdflib_graph and self.sources_valid) """


        # if self.verbose: printDebug("----------")
        if self.verbose: printDebug("Reading: <%s>" % uri, fg="green")
        success = False

        sorted_fmt_opts = try_sort_fmt_opts(self.rdf_format_opts, uri)

        for f in sorted_fmt_opts:
            if self.verbose:
                printDebug(".. trying rdf serialization: <%s>" % f)
            try:
                if f == 'json-ld':
                    if self.verbose:
                        printDebug(
                            "Detected JSONLD - loading data into rdflib.ConjunctiveGraph()",
                            fg='green')
                    temp_graph = rdflib.ConjunctiveGraph()
                else:
                    temp_graph = rdflib.Graph()
                temp_graph.parse(uri, format=f)
                if self.verbose: printDebug("..... success!", bold=True)
                success = True
                self.sources_valid += [uri]
                # ok, so merge
                self.rdflib_graph = self.rdflib_graph + temp_graph
                break
            except:
                temp = None
                if self.verbose: printDebug("..... failed")
                # self._debugGraph()

        if not success == True:
            self.loading_failed(sorted_fmt_opts, uri=uri)
            self.sources_invalid += [uri]