PyQt5 program created with QTdesigner doesnt show any window when opened from terminal

Question

I was working with QT Designer with no issues but today i started a fresh ubuntu 18.04 install, but this time when i run the PyQt5 programs from terminal they doesnt show any windows, same issue when running from atom-runner (It doesnt even show any error)

I exported the .ui files into .py using pyuic5 directly after saving them from Qt Designer, tried a simple blank window and same problem

Any idea how can i fix this?

This is an example of the code, a simple window that should show but for some reason it wont

     # -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'label.ui'
#
# Created by: PyQt5 UI code generator 5.11.3
#
# WARNING! All changes made in this file will be lost!

from PyQt5 import QtCore, QtGui, QtWidgets

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(315, 142)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.label = QtWidgets.QLabel(self.centralwidget)
        self.label.setGeometry(QtCore.QRect(20, 20, 371, 111))
        font = QtGui.QFont()
        font.setPointSize(45)
        self.label.setFont(font)
        self.label.setObjectName("label")
        MainWindow.setCentralWidget(self.centralwidget)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.label.setText(_translate("MainWindow", "DA LABEL"))

Answer 1

To generate a code that can show a window using pyuic you must use the -x option:

pyuic5 input.ui -o output.py -x

The previous command using the -x adds the following code to the end of the file:

if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    MainWindow = QtWidgets.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec_())