README.md edited

.venv/lib/python3.10/site-packages/openpyxl/descriptors/container.py

@@ -0,0 +1,41 @@
+# Copyright (c) 2010-2024 openpyxl
+
+"""
+Utility list for top level containers that contain one type of element
+
+Provides the necessary API to read and write XML
+"""
+
+from openpyxl.xml.functions import Element
+
+
+class ElementList(list):
+
+
+    @property
+    def tagname(self):
+        raise NotImplementedError
+
+
+    @property
+    def expected_type(self):
+        raise NotImplementedError
+
+
+    @classmethod
+    def from_tree(cls, tree):
+        l = [cls.expected_type.from_tree(el) for el in tree]
+        return cls(l)
+
+
+    def to_tree(self):
+        container = Element(self.tagname)
+        for el in self:
+            container.append(el.to_tree())
+        return container
+
+
+    def append(self, value):
+        if not isinstance(value, self.expected_type):
+            raise TypeError(f"Value must of type {self.expected_type} {type(value)} provided")
+        super().append(value)