help needed running a simple function in pyqt5

[menator01]

If spots is less than numbers, you will get duplicates or it may go into an infinity loop.

import random as rnd
import sys
from PyQt5.QtWidgets import (QMainWindow, QApplication, QWidget, QPushButton, QGridLayout, QLabel,
QLineEdit, QListWidget, QMessageBox)


class Window(QMainWindow):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

        # Container
        container = QGridLayout()

        label = QLabel('How many numbers?')
        label2 = QLabel('How many spots?')

        self.entry = QLineEdit()
        self.entry.setPlaceholderText('How many numbers?')
        self.entry.setStyleSheet('border: 1px solid black;')

        self.entry2 = QLineEdit()
        self.entry2.setPlaceholderText('How many spots?')
        self.entry2.setStyleSheet('border: 1px solid black;')

        button = QPushButton('Submit')
        button.clicked.connect(lambda: self.picker(self.entry, self.entry2))
        button2 = QPushButton('Clear')
        button2.clicked.connect(self.clear)

        self.listbox = QListWidget()

        container.addWidget(label, 0, 0, 1, 1)
        container.addWidget(self.entry, 0, 1, 1, 1)
        container.addWidget(label2, 1, 0, 1, 1)
        container.addWidget(self.entry2, 1, 1, 1, 1)
        container.addWidget(button, 2, 0, 1, 1)
        container.addWidget(button2, 2, 1, 1, 1)
        container.addWidget(self.listbox, 3, 0, 1, 2)

        widget = QWidget()
        widget.setLayout(container)
        self.setCentralWidget(widget)

    def clear(self):
        self.listbox.clear()

    def picker(self, how_many, spots):
        messages = ['Spot\'s can not be less than number', 'Only numbers can be entered']
        error = 0
        try:
            spots = int(spots.text())
            how_many = int(how_many.text())
            if spots < how_many:
                text = messages[0]
                error += 1
        except ValueError:
            error += 1
            text = messages[1]

        if error > 0:
            msg = QMessageBox()
            msg.setText(text)
            msg.setIcon(QMessageBox.Warning)
            msg.setWindowTitle('Warning Error!')
            msg.setStandardButtons(QMessageBox.Ok)
            msg.exec_()
        else:
            picks = []
            while len(picks) < how_many:
                pick = rnd.randint(1, spots)
                if str(pick) not in picks:
                    picks.append(f'{pick}')
            nums = ', '.join(picks)
            self.listbox.addItem(nums)
        self.entry.clear()
        self.entry2.clear()


def main():
    app = QApplication(sys.argv)
    window = Window()
    window.show()
    sys.exit(app.exec_())

main()