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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 get_column(self, X, column):
 """Return a column of the given matrix. Args: X: `numpy.ndarray` or `pandas.DataFrame`. column: `int` or `str`. Returns: np.ndarray: Selected column. """

        if isinstance(X, pd.DataFrame):
            return X[column].values

        return X[:, column]