How to use the taurus.external.qt.Qt.QMessageBox function in taurus

if ask:
            op = Qt.QMessageBox.question(self, "Save configuration?",
                                        'Do you want to save the current configuration?\n(if not, any changes will be lost)',
                                        Qt.QMessageBox.Yes | Qt.QMessageBox.No)
            if op != Qt.QMessageBox.Yes:
                return False

        conf = self.getLocalConfig()

        #make sure that no empty measurement groups are written
        for mgname, mgconfig in conf.get('MntGrpConfigs', {}).items():
            if mgconfig is not None and not mgconfig.get('controllers'):
                Qt.QMessageBox.information(self, "Empty Measurement group",
                "The measurement group '%s' is empty. Fill it (or delete it) before applying" % mgname,
                Qt.QMessageBox.Ok)
                self.changeActiveMntGrp(mgname)
                return False

        #check if the currently displayed mntgrp is changed
        if self.ui.channelEditor.getQModel().isDataChanged():
            self._dirtyMntGrps.add(self._localConfig['ActiveMntGrp'])

        door = self.getModelObj()
        door.setExperimentConfiguration(conf, mnt_grps=self._dirtyMntGrps)
        self._originalConfiguration = copy.deepcopy(conf)
        self._dirtyMntGrps = set()
        self.ui.channelEditor.getQModel().setDataChanged(False)
        self._setDirty(False)
        self.emit(Qt.SIGNAL('experimentConfigurationChanged'), copy.deepcopy(conf))
        return True

def onNewSequence(self):
        if Qt.QMessageBox.question(self,
                                   "New sequence",
                                   "Do you want to save existing sequence?",
                                   Qt.QMessageBox.Yes,
                                   Qt.QMessageBox.No) == Qt.QMessageBox.Yes:
            self.onSaveSequence()
        self.tree.clearTree()
        self.newSequenceAction.setEnabled(False)
        self.saveSequenceAction.setEnabled(False)
        self.currentMacroChanged.emit(None)

for aname, my_attr in sorted([(a.name, a) for a in list_attr]):
                if allow_types and my_attr.data_type not in allow_types:
                    continue
                if not expert and my_attr.disp_level == PyTango.DispLevel.EXPERT:
                    continue
                label = aname == my_attr.label and aname.lower(
                ) or "%s (%s)" % (aname.lower(), my_attr.label)
                dct[str(my_device).lower() + '/' + label] = 0
        except PyTango.DevFailed as e:
            self.warning('addAttrToDev(%s): %s' % (my_device, str(e)))
            qmsg = Qt.QMessageBox(Qt.QMessageBox.Critical, '%s Error' %
                                  my_device, '%s not available' % my_device, Qt.QMessageBox.Ok, self)
            qmsg.show()
        except Exception as e:
            self.warning('addAttrToDev(%s): %s' % (my_device, str(e)))
            qmsg = Qt.QMessageBox(Qt.QMessageBox.Critical, '%s Error' %
                                  my_device, str(e), Qt.QMessageBox.Ok, self)
            qmsg.show()
        return dct

perspectives = self.getPerspectivesList()
        if name is None:
            name, ok = Qt.QInputDialog.getItem(
                self, "Save Perspective",
                "Store current settings as the following perspective:",
                perspectives, 0, True
            )
            if not ok:
                return
        if name in perspectives:
            ans = Qt.QMessageBox.question(
                self, "Overwrite perspective?",
                "overwrite existing perspective %s?" % str(name),
                Qt.QMessageBox.Yes, Qt.QMessageBox.No
            )
            if ans != Qt.QMessageBox.Yes:
                return
        self.saveSettings(group="Perspectives/%s" % name)
        self.updatePerspectivesMenu()

def _checkJsonRecorder(self):
        '''Checks if JsonRecorder env var is set and offers to set it'''
        door = self.getModelObj()
        if 'JsonRecorder' not in door.getEnvironment():
            msg = ('JsonRecorder environment variable is not set, but it '
                   + 'is needed for displaying trend plots.\n'
                   + 'Enable it globally for %s?') % door.getFullName()
            result = Qt.QMessageBox.question(
                self.parent(), 'JsonRecorder not set', msg,
                Qt.QMessageBox.Yes | Qt.QMessageBox.No)
            if result == Qt.QMessageBox.Yes:
                door.putEnvironment('JsonRecorder', True)
                self.info('JsonRecorder Enabled for %s' % door.getFullName())

import shutil
                try:
                    bckname = "%s.orig" % fname
                    shutil.copy(fname, bckname)
                except:
                    self.warning("%s will be overwritten but I could not create a backup in %s", fname, bckname)
            #write the data
            try:
                f = open(fname, 'w')
                f.write(xml)
                f.close()
                break
            except Exception, e:
                msg = 'Cannot write to %s: %s' % (fname, str(e))
                self.error(msg)
                Qt.QMessageBox.warning(self, "I/O problem", msg + '\nChoose a different location.', Qt.QMessageBox.Ok, Qt.QMessageBox.NoButton)
                fname = None


        hint = "XML_CONFIG = '%s'" % os.path.relpath(fname, self._confDirectory)
        msg = 'Configuration written in %s' % fname
        self.info(msg)
        Qt.QMessageBox.information(self, "Configuration updated",
                                   msg + '\nMake sure that the .py configuration file in %s contains\n%s' % (self._confDirectory, hint),
                                   Qt.QMessageBox.Ok, Qt.QMessageBox.NoButton)

        return

def getShellCommand(self,obj,wait=False):
        shellCom = obj.getExtensions().get('shellCommand').replace('$NAME',obj._name).replace('$MODEL',obj._name)
        if not wait and not shellCom.endswith('&'): shellCom+=' &' 
        if obj.noPrompt:
            subprocess.call(shellCom,shell=True)
        else:
            yes = Qt.QMessageBox.Ok
            no = Qt.QMessageBox.Cancel
            result = Qt.QMessageBox.question(self.parent(),"Shell command","Would you like to call shell command '" +shellCom+ "' ?",yes, no)
            if result == yes:
                    subprocess.call(shellCom,shell=True) 
        return

bckname = "%s.orig" % fname
                    shutil.copy(fname, bckname)
                except:
                    self.warning(
                        "%s will be overwritten but I could not create a backup in %s", fname, bckname)
            # write the data
            try:
                f = open(fname, 'w')
                f.write(xml)
                f.close()
                break
            except Exception as e:
                msg = 'Cannot write to %s: %s' % (fname, str(e))
                self.error(msg)
                Qt.QMessageBox.warning(
                    self, "I/O problem", msg + '\nChoose a different location.', Qt.QMessageBox.Ok, Qt.QMessageBox.NoButton)
                fname = None

        hint = "XML_CONFIG = '%s'" % os.path.relpath(
            fname, self._confDirectory)
        msg = 'Configuration written in %s' % fname
        self.info(msg)
        Qt.QMessageBox.information(self, "Configuration updated",
                                   msg + '\nMake sure that the .py configuration file in %s contains\n%s' % (
                                       self._confDirectory, hint),
                                   Qt.QMessageBox.Ok, Qt.QMessageBox.NoButton)

        return

f.write(template)
        f.close()
        # if all went ok...
        msg = 'Application project was successfully created.' +\
              'You can find the files in: "%s"' % pdir
        msg += '\nTip: You can install it with:\n\tpip install %s' % pdir
        msg += '\nTip: And then run the application with:\n\t %s' % gui_name
        details = ''
        warnings = self.wizard().getProjectWarnings()
        if warnings:
            msg += '\n\nHowever, some fine-tuning may be needed. Please check the details:\n'
            for _short, _long in warnings:
                details += '- %s: %s\n\n' % (_short, _long)
        logfile.write(msg + details)
        logfile.close()
        dlg = Qt.QMessageBox(Qt.QMessageBox.Information,
                             'Application project created', msg, Qt.QMessageBox.Ok, self)
        dlg.setDetailedText(details)
        dlg.exec_()
        print() 
        print(msg + details)
        print()

try:
            proxy = PyTango.DeviceProxy(my_device)
            timeout = proxy.get_timeout_millis()
            proxy.set_timeout_millis(50)
            proxy.ping()
            list_attr = proxy.attribute_list_query()
            proxy.set_timeout_millis(timeout)

            for aname,my_attr in sorted([(a.name,a) for a in list_attr]):
                if allow_types and my_attr.data_type not in allow_types: continue
                if not expert and my_attr.disp_level==PyTango.DispLevel.EXPERT: continue
                label = aname==my_attr.label and aname.lower() or "%s (%s)"%(aname.lower(),my_attr.label)
                dct[str(my_device).lower()+'/'+label] = 0
        except PyTango.DevFailed,e:
            self.warning('addAttrToDev(%s): %s'%(my_device,str(e)))
            qmsg = Qt.QMessageBox(Qt.QMessageBox.Critical,'%s Error'%my_device,'%s not available'%my_device,Qt.QMessageBox.Ok,self)
            qmsg.show()
        except Exception,e:
            self.warning('addAttrToDev(%s): %s'%(my_device,str(e)))
            qmsg = Qt.QMessageBox(Qt.QMessageBox.Critical,'%s Error'%my_device,str(e),Qt.QMessageBox.Ok,self)
            qmsg.show()
        return dct