有如下log文件，请打印出独立IP，并统计独立IP数，（提示：可使用python，也可使用shell命令行）:
log文件内容:
218.79.251.215 - - [23/May/2006:08:57:44 +0800] "GET /fg172.exe HTTP/1.1" 206 2350253
220.178.150.3 - - [23/May/2006:08:57:40 +0800] "GET /fg172.exe HTTP/1.1" 200 2350253
59.42.2.185 - - [23/May/2006:08:57:52 +0800] "GET /fg172.exe HTTP/1.1" 200 2350253
219.140.190.130 - - [23/May/2006:08:57:59 +0800] "GET /fg172.exe HTTP/1.1" 200 2350253
221.228.143.52 - - [23/May/2006:08:58:08 +0800] "GET /fg172.exe HTTP/1.1" 206 719996
221.228.143.52 - - [23/May/2006:08:58:08 +0800] "GET /fg172.exe HTTP/1.1" 206 713242
221.228.143.52 - - [23/May/2006:08:58:09 +0800] "GET /fg172.exe HTTP/1.1" 206 1200250