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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 RB_to_OPLS(c0, c1, c2, c3, c4, c5):
 """Converts Ryckaert-Bellemans type dihedrals to OPLS type. Parameters c0, c1, c2, c3, c4, c5 : Ryckaert-Belleman coefficients (in kcal/mol) Returns ------- opls_coeffs : np.array, shape=(4,) Array containing the OPLS dihedrals coeffs f1, f2, f3, and f4 (in kcal/mol) """


    f1 = (-1.5 * c3) - (2 * c1)
    f2 = c0 + c1 + c3
    f3 = -0.5 * c3
    f4 = -0.25 * c4
    return np.array([f1, f2, f3, f4])