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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 build_dependencies(self) -> "Dependencies": """ Return `Dependencies` instance containing the build dependencies available on this Package. The ``Package`` class should provide access to the full dependency tree. .. code:: python <ZeppelinPackage> """

        validate_build_dependencies_are_present(self.manifest)

        dependencies = self.manifest["build_dependencies"]
        dependency_packages = {}
        for name, uri in dependencies.items():
            try:
                validate_build_dependency(name, uri)
                dependency_package = Package.from_uri(uri, self.w3)
            except PyEthPMError as e:
                raise FailureToFetchIPFSAssetsError(
                    f"Failed to retrieve build dependency: {name} from URI: {uri}.\n"
                    f"Got error: {e}."
                )
            else:
                dependency_packages[name] = dependency_package

        return Dependencies(dependency_packages)