Return the library instance.  Can generally use slicing to return the library:
            arctic_store[library]

        Parameters
        ----------
        library : `str`
            The name of the library. e.g. 'library' or 'user.library'

def get_library(self, library):
        """
        Return the library instance.  Can generally use slicing to return the library:
            arctic_store[library]

        Parameters
        ----------
        library : `str`
            The name of the library. e.g. 'library' or 'user.library'
        """
        if library in self._library_cache:
            return self._library_cache[library]

        try:
            error = None
            lib = ArcticLibraryBinding(self, library)
            lib_type = lib.get_library_type()
        except (OperationFailure, AutoReconnect) as e:
            error = e

        if error:
            raise LibraryNotFoundException("Library %s was not correctly initialized in %s.\nReason: %r)" %
                                           (library, self, error))
        elif not lib_type:
            raise LibraryNotFoundException("Library %s was not correctly initialized in %s." %
                                           (library, self))
        elif lib_type not in LIBRARY_TYPES:
            raise LibraryNotFoundException("Couldn't load LibraryType '%s' for '%s' (has the class been registered?)" %
                                           (lib_type, library))
        instance = LIBRARY_TYPES[lib_type](lib)
        self._library_cache[library] = instance
        # The library official name may be different from 'library': e.g. 'library' vs 'user.library'
        self._library_cache[lib.get_name()] = instance
        return self._library_cache[library]