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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 setup_releasetype_buttons(self, ):
 """Create a radio button for every releasetype :returns: None :rtype: None :raises: None """

        # we insert the radiobuttons instead of adding them
        # because there is already a spacer in the layout to
        # keep the buttons to the left. To maintain the original order
        # we insert them all to position 0 but in reversed order
        for rt in reversed(self._releasetypes):
            rb = QtGui.QRadioButton(rt)
            self.releasetype_hbox.insertWidget(0, rb)
            self._releasetype_button_mapping[rt] = rb
        # set first radiobutton checked
        if self._releasetypes:
            rt = self._releasetypes[0]
            rb = self._releasetype_button_mapping[rt]
            rb.setChecked(True)
        # if there is only one releasetype hide the buttons
        if len(self._releasetypes) == 1:
            self.releasetype_widget.setVisible(False)