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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 BorueErukhimovich(q, C, r0, s, t):
 """Borue-Erukhimovich model of microphase separation in polyelectrolytes Inputs: ------- ``q``: independent variable ``C``: scaling factor ``r0``: typical el.stat. screening length ``s``: dimensionless charge concentration ``t``: dimensionless temperature Formula: -------- ``C*(x^2+s)/((x^2+s)(x^2+t)+1)`` where ``x=q*r0`` Literature: o Borue and Erukhimovich. Macromolecules (1988) 21 (11) 3240-3249 o Shibayama and Tanaka. J. Chem. Phys (1995) 102 (23) 9392 o Moussaid et. al. J. Phys II (France) (1993) 3 (4) 573-594 o Ermi and Amis. Macromolecules (1997) 30 (22) 6937-6942 """

    x = q * r0
    return C * (x ** 2 + s) / ((x ** 2 + s) * (x ** 2 + t) + 1)