<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def branches_containing(commit):
 """Return a list of branches conatining that commit"""

    lines = run('branch --contains %s' % commit).splitlines()
    return [l.lstrip('* ') for l in lines]