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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 mixing_phases(U):
 """Return the angles and CP phases of the CKM or PMNS matrix in standard parametrization, starting from a matrix with arbitrary phase convention."""

    f = {}
    # angles
    f['t13'] = asin(abs(U[0,2]))
    if U[0,0] == 0:
        f['t12'] = pi/2
    else:
        f['t12'] = atan(abs(U[0,1])/abs(U[0,0]))
    if U[2,2] == 0:
        f['t23'] = pi/2
    else:
        f['t23'] = atan(abs(U[1,2])/abs(U[2,2]))
    s12 = sin(f['t12'])
    c12 = cos(f['t12'])
    s13 = sin(f['t13'])
    c13 = cos(f['t13'])
    s23 = sin(f['t23'])
    c23 = cos(f['t23'])
    # standard phase
    if (s12*s23) == 0 or (c12*c13**2*c23*s13) == 0:
        f['delta'] = 0
    else:
        f['delta'] = -phase((U[0,0].conj()*U[0,2]*U[2,0]*U[2,2].conj()/(c12*c13**2*c23*s13) + c12*c23*s13)/(s12*s23))
    # Majorana phases
    f['delta1']  = phase(exp(1j*f['delta']) * U[0, 2])
    f['delta2']  = phase(U[1, 2])
    f['delta3']  = phase(U[2, 2])
    f['phi1'] = 2*phase(exp(1j*f['delta1']) * U[0, 0].conj())
    f['phi2'] = 2*phase(exp(1j*f['delta1']) * U[0, 1].conj())
    return f