def trim_start(self, n=1):
        """
        Remove items from the start of the list, without touching the parent.
        """
        if len(self.data) > n:
            raise IndexError("Size of trim too large; can't trim %s items "
                             "from a list of size %s." % (n, len(self.data)))
        elif n < 0:
            raise IndexError('Trim size must be >= 0.')
        del self.data[:n]
        del self.items[:n]
        if self.parent:
            self.parent_offset += n
dataset/ETHPy150Open adieu/allbuttonspressed/docutils/statemachine.py/ViewList.trim_start/swapped operands of `>`