PySide QDoubleSpinBox with mathematical operators

superSpinbox.py

class superSpinBox(QDoubleSpinBox):
    """"Spinbox which allows math expressions. Requires 'from __future__ import division' """
    
    def __init__(self, parent=None):
        QDoubleSpinBox.__init__(self, parent)
        
    def validate(self, text, pos):
        return QValidator.Acceptable
    
    def valueFromText(self, text):
        oldValue = self.value()
        text = unicode(text)
        try:
            newValue = eval(text)
        except:
            return oldValue
        else:
            return newValue