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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_non_uniform(p, q, coords, k):
 """Constructs the equation matrix for the finite difference coefficients of non-uniform grids at location k"""

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