How to add a custom minimize button in PyQt5 as i am getting a TypeError?

[ChrisW67]

The min() function is, indeed, a standard Python function but it not the root cause of the message.

The mousePressEvent() function has two arguments:

• the object pointer
• the QMouseEvent

Your implementation only takes one argument.
This works better:

def min(self, event):
    self.setWindowState(self.windowState() | QWindow.Minimized)
    event.accept()

def min(self, event):
    self.setWindowState(self.windowState() | QWindow.Minimized)
    event.accept()

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I am not entirely sure it a clean approach though.
I would also consider:

• making the three buttons actual QPushButtons and doing this plumbing with signal/slot connections rather than hijacking the event handler
• Using layouts to place widgets within the parent widget