def METHOD_NAME(c_string):
    """Given a string of coefficients, returns the polynomial with those coefficients
    INPUT:
        c_string -- string, a a comma-separated string (with no spaces) of rational numbers
    OUTPUT:
        The polynomial with these coefficients
    """
    R = PolynomialRing(QQ, names=('x',))
    (x,) = R._first_ngens(1)
    tup = eval(c_string)
    return sum([tup[i]*x**i for i in range(0,len(tup))])