1， 今天在调用call的时候出错：

File "/share/Public/cmiao/MyScripts/call_snp_pipeline/call_snp_pipeline.py", line 115, in pre_tophat2
call([‘bowtie2-bulid‘, i, prefix_i])
File "/usr/lib64/python2.6/subprocess.py", line 478, in call
p = Popen(*popenargs, **kwargs)
File "/usr/lib64/python2.6/subprocess.py", line 642, in __init__
errread, errwrite)
File "/usr/lib64/python2.6/subprocess.py", line 1234, in _execute_child
raise child_exception
OSError: [Errno 2] No such file or directory