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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 color_group(self, checked=False, test_color=None):
 """Change the color of the group."""

        group = self.tabs.currentWidget()
        if test_color is None:
            newcolor = QColorDialog.getColor(group.idx_color)
        else:
            newcolor = test_color
        group.idx_color = newcolor

        self.apply()