Python error: Type error: POST data should be bytes; also user-agent issue

Question

Using the following code I received an error:

TypeError: POST data should be bytes or an iterable of bytes. It cannot be str

Second concern

Answer 1

data = urllib.parse.urlencode(values)
type(data) #this returns . it's a string

The urllib docs say for urllib.request.Request(url, data ...):

The urllib.parse.urlencode() function takes a mapping or sequence of 2-tuples and returns a string in this format. It should be encoded to bytes before being used as the data parameter. etc etc

(emphasis mine)

So you have a string that looks right, what you need is that string encoded into bytes. And you choose the encoding.

binary_data = data.encode(encoding)

in the above line: encoding can be 'utf-8' or 'ascii' or a bunch of other things. Pick whichever one the server expects.

So you end up with something that looks like:

data = urllib.parse.urlencode(values)
binary_data = data.encode(encoding) 
req = urllib.request.Request(url, binary_data)