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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 _rgb_to_hex(rgbs):
 """Convert rgb to hex triplet"""

    rgbs, n_dim = _check_color_dim(rgbs)
    return np.array(['#%02x%02x%02x' % tuple((255*rgb[:3]).astype(np.uint8))
                     for rgb in rgbs], '|U7')