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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 _interleave(a, b):
 """Interleave arrays a and b; b may have multiple columns and must be shorter by 1. """

    b = np.column_stack([b]) # Turn b into a column array.
    nx, ny = b.shape
    c = np.zeros((nx + 1, ny + 1))
    c[:, 0] = a
    c[:-1, 1:] = b
    return c.ravel()[:-(c.shape[1] - 1)]