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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 csep_close(ra, rb):
 """Return the closest separation vector between each point in one set, and every point in a second set. Parameters ra, rb: float array-like, shape (n, d) and (m, d) in d dimensions. Two sets of points. `ra` is the set of points from which the closest separation vectors to points `rb` are calculated. Returns ------- csep_close: float array-like, shape (n, m, d) csep[i] is the closest separation vector from point ra[j] to any point rb[i]. Note the un-intuitive vector direction. """

    seps = csep(ra, rb)
    seps_sq = np.sum(np.square(seps), axis=-1)

    i_close = np.argmin(seps_sq, axis=-1)

    i_all = list(range(len(seps)))
    sep = seps[i_all, i_close]
    sep_sq = seps_sq[i_all, i_close]
    return sep, sep_sq