Split the data URI on the comma to get the base64 encoded data without the header. Call base64.b64decode
to decode that to bytes. Last, write the bytes to a file.
from base64 import b64decode
data_uri = "data:image/png;base64,iVBORw0KGg..."
# Python 2 and <Python 3.4
header, encoded = data_uri.split("base64,", 1)
data = b64decode(encoded)
# Python 3.4+
# from urllib import request
# with request.urlopen(data_uri) as response:
# data = response.read()
with open("image.png", "wb") as f:
f.write(data)