<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def selectNumber(self):
 """ Select the numerical portion of the text to allow quick editing by the user. """

        le = self.lineEdit()
        text = asUnicode(le.text())
        if self.opts['suffix'] == '':
            le.setSelection(0, len(text))
        else:
            try:
                index = text.index(' ')
            except ValueError:
                return
            le.setSelection(0, index)