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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 add_bias(X):
 """Helper function to add a bias column to the input array X Parameters: X (numpy.ndarray):
 The input data matrix. This must be a numpy.ndarray with 2 dimension wheres every row corresponds to one example of the data set, every column, one different feature. Returns: numpy.ndarray: The same input matrix X with an added (prefix) column of ones. """


  return numpy.hstack((numpy.ones((len(X),1), dtype=X.dtype), X))