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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_install_command(cmd, parse_output, errors, parsed_packages):
    '''
    Executes a command for the install operation.
    If the command fails, its error output will be appended to the errors list.
    If the command succeeds and parse_output is true, updated packages will be appended
    to the parsed_packages dictionary.
    '''
    out = __salt__['cmd.run_all'](
        cmd,
        output_loglevel='trace',
        python_shell=False
    )
    if out['retcode'] != 0:
        if out['stderr']:
            errors.append(out['stderr'])
        else:
            errors.append(out['stdout'])
    elif parse_output:
        parsed_packages.update(_parse_reported_packages_from_install_output(out['stdout']))