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How can I print in an f-string an IP address in the dotted binary notation from the output of inet_pton()?

The following code is supposed to take an IP from its user, convert it to the binary and print it to the screen.
#!/usr/bin/env python3
from socket import inet_aton, inet_pton, AF_INET
ip = input("IP?\n")
ip = inet_pton(AF_INET, ip)
print(f"{ip}")
When given 185.254.27.69 it prints
b'\xb9\xfe\x1bE' .f"{ip:08b}" does not work, perhaps because of the three dots in between the fours octets.. How could I get the dotted binary format of an IP printed on the screen? Any resources of use?

Unless I'm missing something, I don't see a reason to use inet_pton here. It converts to packed bytes, when you want a binary representation of the numbers (I assume):
ip = input("IP?\n")
print('.'.join(f'{int(num):08b}' for num in ip.split('.')))
For the input you supplied:
IP?
185.254.27.69
10111001.11111110.00011011.01000101

this code works for binary ip and keeps leading zeros:
from socket import inet_aton, inet_pton, AF_INET
ip = ip2 = input("IP?\n")
ip = inet_pton(AF_INET, ip)
ip2 = ip2.split(".")
ip3 = ""
for ip in ip2:
ip = int(ip)
if len(ip3) == 0:
zeros = str(bin(ip)[2:]).zfill(8)
ip3 += zeros
else:
zeros = str(bin(ip)[2:]).zfill(8)
ip3 += "." + zeros
print(f"{ip3}")

Python program to convert wildcard mask to netmask

I need help with writing a python program to achieve this task.
I am trying to convert wildcard mask to netmask.
Input:
192.168.0.1 0.0.0.15
Expected output:
192.168.0.1 255.255.255.240

What have you tried? I think it is just xor operator on the bits. Let me know if I'm correct please.
my inputs: 192.168.0.1 0.0.0.15
expected output: 192.168.0.1 255.255.255.240
ip, wcmask = input.split()
netmask='.'.join([str(255^int(i)) for i in wcmask.split('.')])
return '{} {}'.format(ip, netmask)

python2
>>> import ipaddress
>>> print ipaddress.ip_network(u'192.168.0.1/0.0.0.15', strict=False).netmask
255.255.255.240
python3
>>> import ipaddress
>>> print(ipaddress.ip_network('192.168.0.1/0.0.0.15', strict=False).netmask)
255.255.255.240

Convert wildcard to subnet
from cisco_acl import Address
address = Address("192.168.0.1 0.0.0.15")
subnets = address.subnets()
print(subnets)
# ['192.168.0.0 255.255.255.240']
Convert non-contiguous wildcard to list of subnets
from cisco_acl import Address
address = Address("192.168.0.1 0.0.3.15")
subnets = address.subnets()
print(subnets)
# ['192.168.0.0 255.255.255.240',
# '192.168.1.0 255.255.255.240',
# '192.168.2.0 255.255.255.240',
# '192.168.3.0 255.255.255.240']

converting IP string to hex for dpkt.IP

I want to learn packet decoder processing using dpkt. On the site, I saw the following example code:
>>> from dpkt.ip import IP
>>> ip = IP(src='\x01\x02\x03\x04', dst='\x05\x06\x07\x08', p=1)
>>> ...
How do I convert an IP String like '1.2.3.4' to '\x01\x02\x03\x04'?

Use socket.inet_aton:
>>> import socket
>>> socket.inet_aton('1.2.3.4')
'\x01\x02\x03\x04'
To get the dotted decimal back, use socket.inet_ntoa:
>>> socket.inet_ntoa('\x01\x02\x03\x04')
'1.2.3.4'
UPDATE
In Python 3.3+, ipaddress.IPv4Address is another option.
>>> import ipaddress
>>> ipaddress.IPv4Address('1.2.3.4').packed
b'\x01\x02\x03\x04'
>>> ipaddress.IPv4Address(b'\x01\x02\x03\x04')
IPv4Address('1.2.3.4')
>>> str(ipaddress.IPv4Address(b'\x01\x02\x03\x04'))
'1.2.3.4'

Print python os.urandom output on terminal

how can i print the output of os.urandom(n) in terminal?
I try to generate a SECRET_KEY with fabfile and will output the 24 bytes.
Example how i implement both variants in the python shell:
>>> import os
>>> out = os.urandom(24)
>>> out
'oS\xf8\xf4\xe2\xc8\xda\xe3\x7f\xc75*\x83\xb1\x06\x8c\x85\xa4\xa7piE\xd6I'
>>> print out
oS�������5*������piE�I

If what you want is hex-encoded string, use binascii.a2b_hex (or hexlify):
>>> out = 'oS\xf8\xf4\xe2\xc8\xda\xe3\x7f\xc75*\x83\xb1\x06\x8c\x85\xa4\xa7piE\xd6I'
>>> import binascii
>>> print binascii.hexlify(out)
6f53f8f4e2c8dae37fc7352a83b1068c85a4a7706945d649

To use just built-ins, you can get the integer value with ord and then convert that back to a hex number:
list_of_hex = [str(hex(ord(z)))[2:] for z in out]
print " ".join(list_of_hex)
If you just want the hex list, then the str() and [2:] are unnecessary
The output of this and the hexify() version are both type str and should work fine for the web app.

Str to hex in Python

I receive on my socket a 4 bytes value that I want to print as hex value. I am trying:
print "%08x" % (nonce)
However, I get an error message that string can't be converted to hex. Anyone an idea
how this could be quickly resolved?

Use the struct module to unpack the octets received from the network into an actual number. The %08x format will work on the number:
import struct
n, = struct.unpack('>I', nonce)
print "%08x" % n

You most likely have a string containing the bytes. However, to print them as a number you need well.. a number.
You can easily create the hex string you are looking for like this:
''.join('%02x' % ord(x) for x in nonce)
Demo:
>>> nonce = os.urandom(4)
>>> nonce
'X\x19e\x07'
>>> ''.join('%02x' % ord(x) for x in nonce)
'58196507'

Another option is:
from binascii import hexlify
>>> hexlify('a1n4')
'61316e34'

num = "9999"
print hex(int(num))
#0x270f

If your data can be converted to a string, you could use the str.encode() method:
>>> s = "XYZ"
>>> s.encode('hex')
'58595a'