import sys

# This is best for recent Python versions:
try:
    print sys.prefix
    sys.exit(0)
except AttributeError:
    pass

# This doesn't always work:
prefix = ''
path = sys.path[:]
path.reverse()
for dir in path:
	if dir[-11:] == '/lib/python':
		prefix = dir[:-11]
		break
if prefix:
	print prefix
	sys.exit(0)
else:
	sys.exit(1)
