Add struct example and decorator

pythonbpf/decorators.py

@@ -9,11 +9,19 @@ def bpfglobal(func):
     func._is_bpfglobal = True
     return func
 
+
 def map(func):
     """Decorator to mark a function as a BPF map."""
     func._is_map = True
     return func
 
+
+def struct(cls):
+    """Decorator to mark a class as a BPF struct."""
+    cls._is_struct = True
+    return cls
+
+
 def section(name: str):
     def wrapper(fn):
         fn._section = name