<p>它是第四个元素,因此可以使用lambda作为逗号上的键拆分:</p>
<pre><code> s="""
General Motors,Chevrolet,K1500 TAHOE 4WD,18,2900,Standard SUV 4WD
General Motors,Chevrolet,TRAVERSE AWD,19,2750,Standard SUV 4WD
Chrysler Group LLC,Dodge,Durango AWD,19,2750,Standard SUV 4WD
Chrysler Group LLC,Dodge,Durango AWD,16,3400,Standard SUV 4WD
Ford Motor Company,Ford,Expedition 4WD,17,3100,Standard SUV 4WD
Ford Motor Company,Ford,EXPLORER AWD,19,2750,Standard SUV 4WD
"""
print(sorted(s.splitlines()[1:],key=lambda x:x.split(",")[3]))
['Chrysler Group LLC,Dodge,Durango AWD,16,3400,Standard SUV 4WD', 'Ford Motor Company,Ford,Expedition 4WD,17,3100,Standard SUV 4WD', 'General Motors,Chevrolet,K1500 TAHOE 4WD,18,2900,Standard SUV 4WD', 'General Motors,Chevrolet,TRAVERSE AWD,19,2750,Standard SUV 4WD', 'Chrysler Group LLC,Dodge,Durango AWD,19,2750,Standard SUV 4WD', 'Ford Motor Company,Ford,EXPLORER AWD,19,2750,Standard SUV 4WD']
</code></pre>
<p>从文件读取:</p>
<pre><code>with open("in.txt") as f:
print(sorted(f,key=lambda x:x.split(",")[3]))
['Chrysler Group LLC,Dodge,Durango AWD,16,3400,Standard SUV 4WD\n', 'Ford Motor Company,Ford,Expedition 4WD,17,3100,Standard SUV 4WD\n', 'General Motors,Chevrolet,K1500 TAHOE 4WD,18,2900,Standard SUV 4WD\n', 'General Motors,Chevrolet,TRAVERSE AWD,19,2750,Standard SUV 4WD\n', 'Chrysler Group LLC,Dodge,Durango AWD,19,2750,Standard SUV 4WD\n', 'Ford Motor Company,Ford,EXPLORER AWD,19,2750,Standard SUV 4WD']
</code></pre>