def my_det(X):
    '''
    Parameters
    ----------
    X : array_like

    Returns
    -------
    det : float
        Determinant of `a`.
    '''

    a = X
    n = len(X)
    m = len(X[0])
    if n != m:
        raise ValueError("Matrices are of different sizes!")
    eps = 1e-6
    tmp = [[a[i][j] for j in range(m)] for i in range(n)]
    res = 1
    for i in range(n):
        ind = i
        for j in range(i + 1, n):
            ind = i if abs(tmp[j][i]) <= abs(tmp[ind][i]) else j
        if abs(tmp[ind][i]) < eps:
            return 0
        tmp[i], tmp[ind] = tmp[ind], tmp[i]
        if ind != i:
            res *= -1
        res *= tmp[i][i]

        for j in range(i + 1, n):
            tmp[i][j] /= tmp[i][i]
        for j in range(n):
            if abs(tmp[j][i]) > eps and i != j:
                for p in range(i + 1, n):
                    tmp[j][p] -= tmp[i][p] * tmp[j][i]

    det = res
    # Your code here

    return det