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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 style_checkboxes(widget):

 """
 Iterates over widget children to change checkboxes stylesheet.
 
 The default rendering of checkboxes does not allow to tell a focused one
 from an unfocused one.
 """


    ww = widget.findChildren(QCheckBox)
    for w in ww:
        w.setStyleSheet("QCheckBox:focus {border: 1px solid #000000;}")