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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 initialize_from_matrix(cls, matrix, column):
 """Create vector from matrix :param Matrix matrix: The Matrix, which should be used to create the vector. :param integer column: The column of the matrix, which should be used to create the new vector. :raise: Raises an :py:exc:`IndexError` if the matrix does not have the specified column. """

        vec = Vector(matrix.get_height())
        for row in xrange(matrix.get_height()):
            vec.set_value(0, row, matrix.get_value(column, row))
        return vec