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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def check_ok_button(self):
 """Helper to enable or not the OK button."""

        login = self.login.text()
        password = self.password.text()
        url = self.url.text()
        if self.layers.count() >= 1 and login and password and url:
            self.ok_button.setEnabled(True)
        else:
            self.ok_button.setEnabled(False)