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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 tchar(tree_style, cur_level, level, item, size):
 """ Retrieve tree character for particular tree node. """

        if (cur_level == level):
            i1 = '1' if level == 0 else 'x'
            i2 = '1' if item  == 0 else 'x'
            i3 = 'x'
            if size == 1:
                i3 = '1'
            elif item == (size - 1):
                i3 = 'l'
            index = '{}{}{}'.format(i1, i2, i3)
        else:
            index = 'non' if item == (size - 1) else 'ver'
        return TREE_STYLES[tree_style][index]