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