>>> nbre = 18
>>> a = bin (nbre)
>>> a
'0b10010'
>>> b = hex (nbre)
>>> b
'0x12'
>>> c = oct (nbre)
>>> c
'0o22'
>>> d = int (0b10010)
>>> d
18
>>> e = int (0x12)
>>> e
18
>>> f = int (0o22)
>>> f
18
>>> type (a)
<class 'str'>
>>> g = 0b10010
>>> type (g)
<class 'int'>
>>> g
18
>>> 

Utilisation des fonctions intégrées int ( ), bin ( ), hex ( ), oct ( )
Attention ! :

>>> nbre2 = 12.3
>>> h = bin (nbre2)
Traceback (most recent call last):
  File "<pyshell#19>", line 1, in 
    h = bin (nbre2)
TypeError: 'float' object cannot be interpreted as an integer
>>> i = hex (nbre2)
Traceback (most recent call last):
  File "<pyshell#20>", line 1, in 
    i = hex (nbre2)
TypeError: 'float' object cannot be interpreted as an integer