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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 _build_matrix(p, q, deriv):
 """Constructs the equation system matrix for the finite difference coefficients"""

    A = [([1 for _ in range(-p, q+1)])]
    for i in range(1, p + q + 1):
        A.append([j**i for j in range(-p, q+1)])
    return np.array(A)