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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 forward_substitution(matrix_l, matrix_b):
 """ Forward substitution method for the solution of linear systems. Solves the equation :math:`Ly = b` using forward substitution method where :math:`L` is a lower triangular matrix and :math:`b` is a column matrix. :param matrix_l: L, lower triangular matrix :type matrix_l: list, tuple :param matrix_b: b, column matrix :type matrix_b: list, tuple :return: y, column matrix :rtype: list """

    q = len(matrix_b)
    matrix_y = [0.0 for _ in range(q)]
    matrix_y[0] = float(matrix_b[0]) / float(matrix_l[0][0])
    for i in range(1, q):
        matrix_y[i] = float(matrix_b[i]) - sum([matrix_l[i][j] * matrix_y[j] for j in range(0, i)])
        matrix_y[i] /= float(matrix_l[i][i])
    return matrix_y