Archive.insertdoc(d)
TypeError: insertdoc() missing 1 required positional argument: 'd'

doc = Document(name, author, file)
Archive.insertdoc(doc)

def __init__(self):
    self.listdoc = []

def insertdoc(self, d):
    self.listdoc.append(d)

archive = Archive()

doc = Document(name, author, file)
archive.insertdoc(doc)

class Archive():
    def __init__(self):
        self.listdoc = []

    def insertdoc(self, d):
        self.listdoc.append(d)

doc = Document(name, author, file)
archive = Archive()     # Make an instance of class Archive
archive.insertdoc(doc)  # Invoke the insertdoc method of that instance