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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 bures_distance(rho0: Density, rho1: Density) -> float: """Return the Bures distance between mixed quantum states Note: Bures distance cannot be calculated within the tensor backend. """

    fid = fidelity(rho0, rho1)
    op0 = asarray(rho0.asoperator())
    op1 = asarray(rho1.asoperator())
    tr0 = np.trace(op0)
    tr1 = np.trace(op1)

    return np.sqrt(tr0 + tr1 - 2.*np.sqrt(fid))