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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 _normalize_stack(graphobjs):
 """Convert runs of qQ's in the stack into single graphobjs"""

    for operands, operator in graphobjs:
        operator = str(operator)
        if re.match(r'Q*q+$', operator):  # Zero or more Q, one or more q
            for char in operator:  # Split into individual
                yield ([], char)  # Yield individual
        else:
            yield (operands, operator)