How to center a widget in a row in a PyQt grid layout

Question

I'm tryin to center a row with pyqtgrid and I cant figure it out I tried stretches and aligns but it doesn't seem to work not sure what I'm doing wrong. What im looking for is for the left aligned window "Class Subs" to be in the middle of the row that its in here is a MRE

import sys
from PyQt5.QtWidgets import QApplication, QWidget, QTextEdit,QGridLayout
from PyQt5.QtGui import QFont
from PyQt5.QtCore import Qt


class Subs(QTextEdit):
    def __init__(self):
        super().__init__()
        font = QFont("Times New Roman")
        font.setPointSize(30)
        self.setFont(font)
        self.setText("Center Placeholder")
        self.setFixedWidth(500)
        self.setAlignment(Qt.AlignCenter)


class SecondarySub(QTextEdit):
    def __init__(self, parents):
        super().__init__()
        self.parents = parents
        self.setText("placeholder")
        font = QFont("Times New Roman")
        font.setPointSize(30)
        self.setFont(font)
        self.setAlignment(Qt.AlignCenter)
        self.setFixedWidth(1000)
        self.setFixedHeight(100)


class Window(QWidget):
    def __init__(self):
        super().__init__()
        grid_lay = QGridLayout()
        self.setLayout(grid_lay)
        self.widget_sub = Subs()

        self.widget_sub.setFixedWidth(800)
        self.widget_sub.setFixedHeight(50)
        print(self.widget_sub)

        # widgets
        grid_lay.addWidget(SecondarySub(self.widget_sub))
        grid_lay.addWidget(SecondarySub(self.widget_sub))
        grid_lay.addWidget(self.widget_sub)
        grid_lay.setAlignment(Qt.AlignCenter)
        self.setLayout(grid_lay)


app = QApplication(sys.argv)
window = Window()
window.show()
sys.exit(app.exec())