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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 _last_stack_str():
 """Print stack trace from call that didn't originate from here"""

    stack = extract_stack()
    for s in stack[::-1]:
        if op.join('vispy', 'gloo', 'buffer.py') not in __file__:
            break
    return format_list([s])[0]