binascii.Error:即使字符串长度是4的倍数，填充也不正确

我正在尝试通过python代码将base64字符串转换为图像，但是却出现 binascii.Error:填充不正确我的解决方案，但他们仅建议将校验字符串的长度整除4，如果不能通过在base64编码的字符串末尾添加'='使其4整除.请帮忙.

I am trying to convert base64 string to image by python code, but I am getting binascii.Error: Incorrect padding I have gone through with my solution but they only suggest check string length is divisible 4, if not make it divisible by 4 by adding '=' characters at the end of base64 encoded sting. Please help in this.

PYTHON代码:(请从驱动器中检查代码以获取可见度更高

PYTHON CODE: (please check code from drive for more visibility)

import base64

strOne= 'data:image/png;base64,iVBORw0KGgoAAAANSU...string has 200000 character thats why I couldn t paste'
 print 'strOne Length',len(strOne)
 print 'StrOne Length is completely divisible by 4 (len%4),(len/4):', len(strOne)%4,len(strOne)/4

 with open("imageToSave.png", "wb") as fh:
     fh.write(strOne.strip().decode('base64'))

输出:

strOne Length 200000
StrOne Length is completely divisible by 4 (len%4),(len/4): 0 50000
Traceback (most recent call last):
  File "/tests.py", line 13, in <module>
    fh.write(strOne.strip().decode('base64'))
  File "/usr/lib/python2.7/encodings/base64_codec.py", line 42, in base64_decode
    output = base64.decodestring(input)
  File "/usr/lib/python2.7/base64.py", line 328, in decodestring
    return binascii.a2b_base64(s)
binascii.Error: Incorrect padding