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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 inputs_from_dataframe(df, delays=(1, 2, 3), inputs=(1, 2, -1), outputs=None, normalize=True, verbosity=1):
 """ Build a sequence of vectors suitable for "activation" by a neural net Identical to `dataset_from_dataframe`, except that only the input vectors are returned (not a full DataSet instance) and default values for 2 arguments are changed: outputs: None And only the input vectors are return """

    ds = input_dataset_from_dataframe(df=df, delays=delays, inputs=inputs, outputs=outputs,
                                      normalize=normalize, verbosity=verbosity)
    return ds['input']