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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 solve(self, x0, params=(), internal_x0=None, solver=None, attached_solver=None, **kwargs):
 """ Solve with user specified ``solver`` choice. Parameters x0: 1D array of floats Guess (subject to ``self.post_processors``) params: 1D array_like of floats Parameters (subject to ``self.post_processors``) internal_x0: 1D array of floats When given it overrides (processed) ``x0``. ``internal_x0`` is not subject to ``self.post_processors``. solver: str or callable or None or iterable of such if str: uses _solve_``solver``(\*args, \*\*kwargs). if ``None``: chooses from PYNEQSYS_SOLVER environment variable. if iterable: chain solving. attached_solver: callable factory Invokes: solver = attached_solver(self). Returns ------- array: solution vector (post-processed by self.post_processors) dict: info dictionary containing 'success', 'nfev', 'njev' etc. Examples -------- [0.841163901914009663684741869855] [0.158836098085990336315258130144] """

        if not isinstance(solver, (tuple, list)):
            solver = [solver]
        if not isinstance(attached_solver, (tuple, list)):
            attached_solver = [attached_solver] + [None]*(len(solver) - 1)
        _x0, self.internal_params = self.pre_process(x0, params)
        for solv, attached_solv in zip(solver, attached_solver):
            if internal_x0 is not None:
                _x0 = internal_x0
            elif self.internal_x0_cb is not None:
                _x0 = self.internal_x0_cb(x0, params)

            nfo = self._get_solver_cb(solv, attached_solv)(_x0, **kwargs)
            _x0 = nfo['x'].copy()
        self.internal_x = _x0
        x0 = self.post_process(self.internal_x, self.internal_params)[0]
        return x0, nfo