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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 _getMethodNamePrefix(self, node):
 """ Return the prefix of this method based on sibling methods. @param node: the current node """

        targetName = node.name
        for sibling in node.parent.nodes_of_class(type(node)):
            if sibling is node:
                # We are on the same node in parent so we skip it.
                continue
            prefix = self._getCommonStart(targetName, sibling.name)
            if not prefix.rstrip('_'):
                # We ignore prefixes which are just underscores.
                continue
            return prefix

        return ''