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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 staggered_positions(n_channels):
 """Generate channel positions for a staggered probe."""

    i = np.arange(n_channels - 1)
    x, y = (-1) ** i * (5 + i), 10 * (i + 1)
    pos = np.flipud(np.r_[np.zeros((1, 2)), np.c_[x, y]])
    return pos