diff --git a/docs/_ext/github_links.py b/docs/_ext/github_links.py
index 32af97186d..08f4161a01 100644
--- a/docs/_ext/github_links.py
+++ b/docs/_ext/github_links.py
@@ -41,10 +41,10 @@ class CodeLocator(ast.NodeVisitor):
                 file = module_name_to_file_path(node.module)
                 file_contents = file.read_text(encoding="utf-8")
                 locator = CodeLocator.from_code(file_contents)
-                self.import_locations |= locator.import_locations
-                self.import_locations |= {
-                    n: node.module for n in locator.node_line_numbers if "." not in n
-                }
+                self.import_locations.update(locator.import_locations)
+                self.import_locations.update(
+                    {n: node.module for n in locator.node_line_numbers if "." not in n}
+                )
             else:
                 self.import_locations[alias.name] = ("." * node.level) + (
                     node.module or ""