in tools/util.py [0:0]
def hash_file(hash_obj, path):
"""Hash the contents of a file.
Args:
hash_obj: an open hash object, e.g. hashlib.sha1().
path: path to the file to hash.
Returns:
The passed-in hash_obj.
"""
with open(path, 'rb') as f:
while True:
b = f.read(8192)
if not b:
break
hash_obj.update(b)
return hash_obj