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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 update_logo_preview(self):
 """Update logo based on the current logo path."""

        logo_path = self.organisation_logo_path_line_edit.text()
        if os.path.exists(logo_path):
            icon = QPixmap(logo_path)
            label_size = self.organisation_logo_label.size()
            label_size.setHeight(label_size.height() - 2)
            label_size.setWidth(label_size.width() - 2)
            scaled_icon = icon.scaled(
                label_size, Qt.KeepAspectRatio)
            self.organisation_logo_label.setPixmap(scaled_icon)
        else:
            self.organisation_logo_label.setText(tr("Logo not found"))