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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 dry_run(command, dry_run):
 """Executes a shell command unless the dry run option is set"""

    if not dry_run:
        cmd_parts = command.split(' ')
        # http://plumbum.readthedocs.org/en/latest/local_commands.html#run-and-popen
        return local[cmd_parts[0]](cmd_parts[1:])
    else:
        log.info('Dry run of %s, skipping' % command)
    return True