def onShortcutUnindentWithBackspace(self):
        """Backspace pressed, unindent
        """
        assert self._qpart.textBeforeCursor().endswith(self.text())

        charsToRemove = len(self._qpart.textBeforeCursor()) % len(self.text())
        if charsToRemove == 0:
            charsToRemove = len(self.text())

        cursor = self._qpart.textCursor()
        cursor.setPosition(cursor.position() - charsToRemove, QTextCursor.KeepAnchor)
        cursor.removeSelectedText()
def airgap(airgap, ax=0):
    """creates plot of flux density in airgap"""
    if ax == 0:
        ax = plt.gca()
    ax.set_title('Airgap Flux Density [T]')
    ax.plot(airgap['pos'], airgap['B'],
            label='Max {:4.2f} T'.format(max(airgap['B'])))
    ax.plot(airgap['pos'], airgap['B_fft'],
            label='Base Ampl {:4.2f} T'.format(airgap['Bamp']))
    ax.set_xlabel('Position/°')
    ax.legend()
    ax.grid(True)