Bug path parser (#151)

* bugs: path parser, write

* bug: skeleton writer:

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Co-authored-by: anna-grim <[email protected]>

Author: anna-grim

src/segmentation_skeleton_metrics/skeleton_graph.py

@@ -296,7 +296,7 @@ def to_zipped_swc(self, zip_writer):
         # Subroutines
         def write_entry(node, parent):
             x, y, z = tuple(self.voxels[i] * self.anisotropy)
-            r = self.node_radius[node] if preserve_radius else 2
+            r = 2 if self.is_groundtruth else 3
             node_id = len(node_to_idx) + 1
             node_to_idx[node] = node_id
             text_buffer.write("\n" + f"{node_id} 2 {x} {y} {z} {r} {parent}")