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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 execute(source, optimize=True, output=sys.stdout, input=sys.stdin, steps=-1):
 """Compiles and runs program, returning the machine used to execute the code. Args: optimize: Whether to optimize the code after parsing it. output: Stream which program can write output to. input: Stream which program can read input from. steps: An optional maximum number of instructions to execute on the virtual machine. Set to -1 for no limit. Returns: A Machine instance. """

    from crianza import compiler
    code = compiler.compile(parser.parse(source), optimize=optimize)
    machine = Machine(code, output=output, input=input)
    return machine.run(steps)