New Feature to add Tasks and Task Relationships in the python ifcopenshell API (#1432)

src/ifcopenshell-python/ifcopenshell/api/sequence/assign_task_successor.py

@@ -0,0 +1,25 @@
+import ifcopenshell
+import ifcopenshell.api
+
+
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {
+            "task": None,
+            "sequence_type":"FINISH_START",
+            "successor_task": None,
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        #TODO: tasks can only have one relationship between oneanother: if a relationship is already assigned, it should overide the previous one's settings.
+        rel_sequence = self.file.create_entity("IfcRelSequence",**{
+                "GlobalId": ifcopenshell.guid.new(),
+                "OwnerHistory": ifcopenshell.api.run("owner.create_owner_history", self.file),
+                "RelatingProcess": self.settings["task"],
+                "SequenceType": self.settings["sequence_type"],
+                "RelatedProcess": self.settings["successor_task"],
+            })
+        return rel_sequence