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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 set_colors(self, text='black', background='white'):
 """ Sets the colors of the text area. """

        if self._multiline: self._widget.setStyleSheet("QTextEdit {background-color: "+str(background)+"; color: "+str(text)+"}")
        else:               self._widget.setStyleSheet("QLineEdit {background-color: "+str(background)+"; color: "+str(text)+"}")