many changes

pydiffvg/gmtools.py

@@ -0,0 +1,23 @@
+#!/usr/bin/env ipython
+from pathlib import Path
+
+class GradientMesh:
+    """ Class representing a gradient mesh. """
+    def __init__(self):
+        raise NotImplementedError
+
+    def render(self):  # TODO type
+        raise NotImplementedError
+
+    def to_str(self) -> str:
+        raise NotImplementedError
+
+    @classmethod
+    def from_str(cls, str):
+        raise NotImplementedError
+
+    def __repr__(self) -> str:
+        raise NotImplementedError
+
+def read_gm(filename: Path) -> GradientMesh:
+    raise NotImplementedError