python--md5

import hashlib
import os


#字符串md5
def string_md5(str_value):
    if str_value:
        hashmd5 = hashlib.md5()
        hashmd5.update(str_value.encode('utf-8'))
        str_md5 = hashmd5.hexdigest()
        return str_md5
    else:
        return None


# 字符串md5
def bytes_string_md5(str_value):
    if str_value:
        hashmd5 = hashlib.md5()
        hashmd5.update(str_value)
        str_md5 = hashmd5.hexdigest()
        return str_md5
    else:
        return None


#文件md5
def file_md5(pathandname):
    if os.path.isfile(pathandname):
        hashmd5 = hashlib.md5()
        file = open(pathandname, 'rb')
        while True:
            b = file.read(1024)
            if not b:
                break
            hashmd5.update(b)
        file.close()
        return hashmd5.hexdigest()
    else:
        return None