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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _initUI(self):
 """Creates the inital layout with all subwidgets. The layout is a `QHBoxLayout`. Each time a radio button is selected or unselected, a slot `DelimiterSelectionWidget._delimiter` is called. Furthermore the `QLineEdit` widget has a custom regex validator `DelimiterValidator` enabled. """

        #layout = QtGui.QHBoxLayout(self)

        self.semicolonRadioButton = QtGui.QRadioButton('Semicolon')
        self.commaRadioButton = QtGui.QRadioButton('Comma')
        self.tabRadioButton = QtGui.QRadioButton('Tab')
        self.otherRadioButton = QtGui.QRadioButton('Other')
        self.commaRadioButton.setChecked(True)

        self.otherSeparatorLineEdit = QtGui.QLineEdit(self)
        #TODO: Enable this or add BAR radio and option.
        self.otherSeparatorLineEdit.setEnabled(False)

        self.semicolonRadioButton.toggled.connect(self._delimiter)
        self.commaRadioButton.toggled.connect(self._delimiter)
        self.tabRadioButton.toggled.connect(self._delimiter)

        self.otherRadioButton.toggled.connect(self._enableLine)
        self.otherSeparatorLineEdit.textChanged.connect(lambda: self._delimiter(True))
        self.otherSeparatorLineEdit.setValidator(DelimiterValidator(self))

        currentLayout = self.layout()
        # unset and delete the current layout in order to set a new one
        if currentLayout is not None:
            del currentLayout

        layout = QtGui.QHBoxLayout()
        layout.addWidget(self.semicolonRadioButton)
        layout.addWidget(self.commaRadioButton)
        layout.addWidget(self.tabRadioButton)
        layout.addWidget(self.otherRadioButton)
        layout.addWidget(self.otherSeparatorLineEdit)
        self.setLayout(layout)