fixup missing format

pandas/_libs/tslibs/offsets.pyx

@@ -427,7 +427,7 @@ class _BaseOffset(object):
             nint = int(n)
         except (ValueError, TypeError):
             raise TypeError('`n` argument must be an integer, '
-                            'got {ntype}'.format(type(n)))
+                            'got {ntype}'.format(ntype=type(n)))
         if n != nint:
             raise ValueError('`n` argument must be an integer, '
                              'got {n}'.format(n=n))