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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 _is_epsilon_nash(x, g, epsilon, indptr=None):
 """ Determine whether `x` is an `epsilon`-Nash equilibrium of `g`. Parameters x : array_like(float, ndim=1) Array of flattened mixed action profile of length equal to n_0 + i's mixed action. g : NormalFormGame epsilon : scalar(float) indptr : array_like(int, ndim=1), optional(default=None) Array of index pointers of length N+1, where `indptr[0] = 0` and `indptr[i+1] = indptr[i] + n_i`. Created internally if None. Returns ------- bool """

    if indptr is None:
        indptr = np.empty(g.N+1, dtype=int)
        indptr[0] = 0
        indptr[1:] = np.cumsum(g.nums_actions)

    action_profile = _get_action_profile(x, indptr)
    return g.is_nash(action_profile, tol=epsilon)