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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 densities_close(rho0: Density, rho1: Density, tolerance: float = TOLERANCE) -> bool: """Returns True if densities are almost identical. Closeness is measured with the metric Fubini-Study angle. """

    return vectors_close(rho0.vec, rho1.vec, tolerance)