def add_source_code_and_doc(f):
    @wraps(f)
    def f_with_source_and_doc(request, title, sidebar_items, 
                              *args, **kwargs):
        doc = f.__doc__
        if doc is None:
            doc = ""
        else:
            doc = textwrap.dedent(f.__doc__)
        
        src_lines, num_lines = inspect.getsourcelines(f)
        start_line = end_line = None
        for i, line in enumerate(src_lines):
            if start_line is None or end_line is None: 
                if '#start_code' in line:
                    start_line = i+1
                if '#end_code' in line:
                    end_line = i
            else:
                break
        if end_line is None:
            end_line = num_lines - 1
        if start_line is None:
            start_line = 1
            
        code = ''.join(src_lines[start_line: end_line])   
        code = textwrap.dedent(code)
        return f(request, code = code, title = title,
                 doc = doc, sidebar_items = sidebar_items)
    return f_with_source_and_doc
Instrospects the function and adds source code and the doc string to 
dataset/ETHPy150Open pgollakota/django-chartit/demoproject/utils/decorators.py/add_source_code_and_doc