Parenting PySide2 Widget to main Maya window

I designed a prototype UI from QtDesigner and converted the .ui file to .py

After some combining this and that from internet i managed to see my prototype but i couldn't parent it to the main Maya window just like regular cmds UI.

from maya import OpenMayaUI as omui 
from PySide2 import QtCore, QtGui, QtWidgets
from shiboken2 import wrapInstance

mayaMainWindowPtr = omui.MQtUtil.mainWindow() 
mayaMainWindow= wrapInstance(long(mayaMainWindowPtr), QtWidgets.QWidget)

class Ui_Form(QtWidgets.QWidget):
    def setupUi(self, Form, parent=mayaMainWindow):
        Form.setObjectName("Form")
        Form.resize(480, 640)
        self.verticalLayoutWidget = QtWidgets.QWidget(Form)
        self.verticalLayoutWidget.setGeometry(QtCore.QRect(170, 130, 261, 251))
        self.verticalLayoutWidget.setObjectName("verticalLayoutWidget")
        self.verticalLayout = QtWidgets.QVBoxLayout(self.verticalLayoutWidget)
        self.verticalLayout.setContentsMargins(0, 0, 0, 0)
        self.verticalLayout.setObjectName("verticalLayout")
        self.radioButton = QtWidgets.QRadioButton(self.verticalLayoutWidget)
        self.radioButton.setObjectName("radioButton")
        self.verticalLayout.addWidget(self.radioButton)
        self.radioButton_2 = QtWidgets.QRadioButton(self.verticalLayoutWidget)
        self.radioButton_2.setObjectName("radioButton_2")
        self.verticalLayout.addWidget(self.radioButton_2)
        self.toolButton = QtWidgets.QToolButton(self.verticalLayoutWidget)
        self.toolButton.setObjectName("toolButton")
        self.verticalLayout.addWidget(self.toolButton)
        self.checkBox = QtWidgets.QCheckBox(Form)
        self.checkBox.setGeometry(QtCore.QRect(150, 530, 70, 17))
        self.checkBox.setObjectName("checkBox")

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

    def retranslateUi(self, Form):
        Form.setWindowTitle(QtWidgets.QApplication.translate("Form", "Form", None, -1))
        self.radioButton.setText(QtWidgets.QApplication.translate("Form", "RadioButton", None, -1))
        self.radioButton_2.setText(QtWidgets.QApplication.translate("Form", "RadioButton", None, -1))
        self.toolButton.setText(QtWidgets.QApplication.translate("Form", "...", None, -1))
        self.checkBox.setText(QtWidgets.QApplication.translate("Form", "CheckBox", None, -1))



if __name__ == "__main__":
    Form = QtWidgets.QWidget()
    ui = Ui_Form()
    ui.setupUi(Form)
    Form.show()

I also tried adding self.setWindowFlags(QtCore.Qt.WindowStaysOnTopHint) to the setupUi method and loading the .ui file with pyside2uic.loadUiType but still no result.