<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def solve( solver, mzn, *dzn_files, data=None, include=None, stdlib_dir=None, globals_dir=None, allow_multiple_assignments=False, output_mode='item', timeout=None, two_pass=None, pre_passes=None, output_objective=False, non_unique=False, all_solutions=False, num_solutions=None, free_search=False, parallel=None, seed=None, **kwargs ):
 """Flatten and solve a MiniZinc program. Parameters solver : Solver The ``Solver`` instance to use. mzn : str The path to the minizinc model file. *dzn_files A list of paths to dzn files to attach to the minizinc execution, provided as positional arguments; by default no data file is attached. data : list of str Additional data as a list of strings containing dzn variables assignments. include : str or list One or more additional paths to search for included ``.mzn`` files. stdlib_dir : str The path to the MiniZinc standard library. Provide it only if it is different from the default one. globals_dir : str The path to the MiniZinc globals directory. Provide it only if it is different from the default one. allow_multiple_assignments : bool Whether to allow multiple assignments of variables. Sometimes is convenient to simply let the data file override the value already assigned in the minizinc file. Default is ``False``. output_mode : {'item', 'dzn', 'json'} The desired output format. The default is ``'item'`` which outputs a stream of strings as returned by the ``solns2out`` tool, formatted according to the output statement of the MiniZinc model. The ``'dzn'`` and ``'json'`` formats output a stream of strings formatted in dzn and json respectively. timeout : int The timeout in seconds for the flattening + solving process. two_pass : bool or int If ``two_pass`` is True, then it is equivalent to the ``--two-pass`` option for the ``minizinc`` executable. If ``two_pass`` is an integer ``<n>``, instead, it is equivalent to the ``-O<n>`` option for the ``minizinc`` executable. pre_passes : int Equivalent to the ``--pre-passes`` option for the ``minizinc`` executable. output_objective : bool Equivalent to the ``--output-objective`` option for the ``minizinc`` executable. Adds a field ``_objective`` to all solutions. non_unique : bool Equivalent to the ``--non-unique`` option for the ``minizinc`` executable. all_solutions : bool Whether all the solutions must be returned. This option might not work if the solver does not support it. Default is ``False``. num_solutions : int The upper bound on the number of solutions to be returned. This option might not work if the solver does not support it. Default is ``1``. free_search : bool If True, instruct the solver to perform free search. parallel : int The number of parallel threads the solver can utilize for the solving. seed : int The random number generator seed to pass to the solver. **kwargs Additional arguments to pass to the solver, provided as additional keyword arguments to this function. Check the solver documentation for the available arguments. Returns ------- Object wrapping the executed process. """


    args = _solve_args(
        solver, timeout=timeout, two_pass=two_pass, pre_passes=pre_passes,
        output_objective=output_objective, non_unique=non_unique,
        all_solutions=all_solutions, num_solutions=num_solutions,
        free_search=free_search, parallel=parallel, seed=seed, **kwargs
    )

    args += _flattening_args(
        mzn, *dzn_files, data=data, stdlib_dir=stdlib_dir,
        globals_dir=globals_dir, output_mode=output_mode, include=include,
        allow_multiple_assignments=allow_multiple_assignments
    )

    input = mzn if args[-1] == '-' else None

    t0 = _time()

    try:
        proc = _run_minizinc_proc(*args, input=input)
    except RuntimeError as err:
        raise MiniZincError(mzn_file, args) from err

    solve_time = _time() - t0
    logger.info('Solving completed in {:>3.2f} sec'.format(solve_time))

    return proc