题目：
1 Sickle 为 29 Knuts
1 Galleon 为 17 Sickle
问现有300 Galleon，用Sympy设Sickles，Galleon，Knuts三个未知数，并算出300 Galleon = 多少 Knuts。
我是这么写的：
import sympy as sp
sp.init_printing()
Knut = sp.symbols('Knut')
Sickles = sp.symbols('Sickles')
Sickles = 29*Knut
Galleon = 17*Sickles
lucre = sp.solve(300*Galleon, Knut)
print (lucre)
最终显示为[0]，我想知道我哪里错了，应该咋改？
（最终结果应该是 ‘xxxx Knuts’ 的形式）
import sympy as sp
Knut = sp.symbols('Knut')
Sickles = sp.symbols('Sickles')
Galleon = sp.symbols('Galleon')
lucre = sp.solve(Knut*29-Sickle,Sickle * 17 - Galleon, Galleon-300, [Knut, Sickle, Galleon ])
print (lucre)