Add API documentation for classification module

src/ifcopenshell-python/ifcopenshell/api/classification/remove_classification.py

@@ -18,11 +18,27 @@
 
 
 class Usecase:
-    def __init__(self, file, **settings):
+    def __init__(self, file, classifcation=None):
+        """Removes an IfcClassification from the project and all references
+
+        The classification and all of its relationships, children references,
+        and relationships between objectse and child references are completely
+        removed from a project.
+
+        :param classification: The IfcClassification entity you want to remove
+        :type classification: ifcopenshell.entity_instance.entity_instance
+        :return: None
+        :rtype: None
+
+        Example::
+
+            classification = model.by_type("IfcClassification")[0]
+            ifcopenshell.api.run("classification.remove_classification", model,
+                classification=classification)
+        """
+
         self.file = file
-        self.settings = {"classification": None}
-        for key, value in settings.items():
-            self.settings[key] = value
+        self.settings = {"classification": classification}
 
     def execute(self):
         references = self.get_references(self.settings["classification"])