Bob_widget = widget['Bob']  # lookup widget by objectName
assert Bob_widget.layout.coordinates == (0, 0)

import sys
from collections import namedtuple

from PyQt5.QtWidgets import (QApplication, QMainWindow, QWidget, QGridLayout,
                             QLabel, QDoubleSpinBox)

gui_userinput = namedtuple('gui_userinput', ['key', 'string', 'value', 'range'])

variable_a = gui_userinput(key='variable_a', string='Variable A', value=165.00,
                           range=(0.00, 10000.00))
variable_b = gui_userinput(key='variable_b', string='Variable B', value=135.00,
                           range=(0.00, 10000.00))

gui_userinput_order = (variable_a, variable_b)


class Gui(QMainWindow):
    def __init__(self, parent=None):

        super(Gui, self).__init__(parent)

        self.setObjectName('toplevel')
        self.setupUi()

    def setupUi(self):

        centralWidget = QWidget()
        centralWidget.setObjectName('centralwidget')
        self.setCentralWidget(centralWidget)

        centralLayout = QGridLayout()
        self.setObjectName('centrallayout')

        for i, widget in enumerate(gui_userinput_order):

            wlabel = QLabel(widget.string)
            wlabel.setObjectName(widget.key + '_label')

            wbox = QDoubleSpinBox()
            wbox.setObjectName(widget.key)
            wbox.setRange(*widget.range)
            wbox.setValue(widget.value)

            centralLayout.addWidget(wlabel, 0, i)
            centralLayout.addWidget(wbox, 1, i)

        centralWidget.setLayout(centralLayout)


if __name__ == '__main__':

    app = QApplication(sys.argv)
    ui = Gui()
    ui.show()
    sys.exit(app.exec_())

widget_0_0 = self.ui.centralWidget().layout()
            .itemAtPosition(0, 0).widget()

import sys
from PyQt5.QtWidgets import QApplication, QDoubleSpinBox, QLabel

import mini_ui

app = QApplication(sys.argv)


class TestMainGUi:

    def setup(self):
        self.ui = mini_ui.Gui()

    def test_all_widgets_exist(self):
        """The user finds the expected labels and doublespinboxes."""
        for widget in mini_ui.gui_userinput_order:
            found_box = self.ui.findChild(QDoubleSpinBox, widget.key)
            assert found_box.value() == widget.value
            found_label = self.ui.findChild(QLabel, widget.key + '_label')
            assert found_label.text() == widget.string

    def test_label_0_0(self):
        """The user sees a label for 'Variable A' in the top left corner."""
        label_a = self.ui.findChild(QLabel, 'variable_a_label')
        print('Found', label_a, 'named', label_a.objectName(), 'in GUI.')
        widget_0_0 = self.ui.centralWidget().layout()
            .itemAtPosition(0, 0).widget()
        print('Found widget type', type(widget_0_0), 'at grid 0, 0')
        print('It is named: ', widget_0_0.objectName())

        assert widget_0_0.text() == 'Variable A'
        assert widget_0_0 is label_a

    def test_alternate_widget_acces(self):
        """Just hacking away trying to find a more terse widget reference"""
        label_a = self.ui.findChild(QLabel, 'variable_a_label')

        assert 1 == 1

    def teardown(self):
        pass