"Traceback (most recent call last):
File "./build.py", line 102, in <module>
main(sys.argv[1:])
File "./build.py", line 94, in main
setup()
File "./build.py", line 24, in setup
call(['curl', '-O', PROTOBUF_URL])
File "/usr/lib/python2.7/subprocess.py", line 522, in call
return Popen(*popenargs, **kwargs).wait()
File "/usr/lib/python2.7/subprocess.py", line 710, in __init__
errread, errwrite)
File "/usr/lib/python2.7/subprocess.py", line 1327, in _execute_child
raise child_exception
OSError: [Errno 20] Not a directory"