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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 balanced_binary_tree(n_leaves):
 """ Create a balanced binary tree """

    def _balanced_subtree(leaves):
        if len(leaves) == 1:
            return leaves[0]
        elif len(leaves) == 2:
            return (leaves[0], leaves[1])
        else:
            split = len(leaves) // 2
            return (_balanced_subtree(leaves[:split]),
                    _balanced_subtree(leaves[split:]))

    return _balanced_subtree(np.arange(n_leaves))