import hashlib
import os


def sha_file(f):
    if f not in set(os.listdir(".")):
        return "None:::sha_file_end"
    else:
        sha = hashlib.sha256()
        with open(f, encoding="utf-8") as fd:
            file_buffer = fd.read(128).encode("utf-8")
            while len(file_buffer) > 0:
                sha.update(file_buffer)
                file_buffer = fd.read(128).encode("utf-8")
            h = sha.digest()
            return "".join(["%.2x" % i for i in h]) + ":::sha_file_end"


def reload(mod):
    import sys

    mod_name = mod.__name__
    try:
        del sys.modules[mod_name]
        __import__(mod_name)
    except:
        pass