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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 concat(x, y, axis=0):
 """Concatenate a sequence of pandas or numpy objects into one entity."""

    if all([isinstance(df, (pd.DataFrame, pd.Series)) for df in [x, y]]):
        return pd.concat([x, y], axis=axis)
    else:
        if axis == 0:
            return np.concatenate([x, y])
        else:
            return np.column_stack([x, y])