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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 font(self, prefix, size):
 """Return a QFont corresponding to the given prefix and size."""

        font = QFont(self.fontname[prefix])
        font.setPixelSize(size)
        if prefix[-1] == 's':  # solid style
            font.setStyleName('Solid')
        return font