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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 _check_y(y):
 """ Makes sure a `y` argument is a vliad numpy dataset. """

  if not isinstance(y, np.ndarray):
    raise TypeError("y must be numpy array. Typically y contains "
                    "the entire test set labels. Got " + str(y) + " of type " + str(type(y)))