QPushButton with embedded QLabel

gistfile1.txt

from PyQt5 import QtWidgets
import sys

app = QtWidgets.QApplication(sys.argv)
window = QtWidgets.QWidget()
mainLayout = QtWidgets.QGridLayout(window)
labels = []
for r in range(3):
    for c in range(4):
        button = QtWidgets.QPushButton()
        label = QtWidgets.QLabel()
        # possible workaround:
        # button.sizeHint = label.sizeHint
        mainLayout.addWidget(button, r, c)
        button.setStyleSheet('QPushButton {border: none;}')
        buttonLayout = QtWidgets.QVBoxLayout(button)
        buttonLayout.setContentsMargins(0, 0, 0, 0)
        labels.append(label)
        buttonLayout.addWidget(label)

le = QtWidgets.QLineEdit(placeholderText='button text')
mainLayout.addWidget(le, mainLayout.rowCount(), 0, 1, 4)
le.textChanged.connect(lambda text: [l.setText(text) for l in labels])

window.show()
sys.exit(app.exec_())