Fix python 3.9 not supporting pipe operator in type hints

SylviaWhittle · SylviaWhittle · commit 578c2fc7c15d · 2024-04-22T15:50:18.000+01:00
diff --git a/topofileformats/spm.py b/topofileformats/spm.py
@@ -1,5 +1,6 @@
 """For decoding and loading .spm AFM file format into Python Numpy arrays."""
 
+from __future__ import annotations
 from pathlib import Path
 
 import pySPM
