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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def security_label(self, name, description=None, color=None):
 """Return instance of SecurityLabel. .. note:: The provided security label will be create if it doesn't exist. If the security label already exists nothing will be changed. Args: name (str):
 The value for this security label. description (str):
 A description for this security label. color (str):
 A color (hex value) for this security label. Returns: obj: An instance of SecurityLabel. """

        label = SecurityLabel(name, description, color)
        for label_data in self._labels:
            if label_data.name == name:
                label = label_data
                break
        else:
            self._labels.append(label)
        return label