How to reinterpret bits of float as int in python

I had to write code that printed out bits of floating point number (in hexadecimal). For C++, the first thing that came to mind was std::cout << std::hex << *reinterpret_cast<uint32_t*>(&x); where x is a floating point variable that stores the original number.

However, when I tried the same problem in python, I just couldn't come up with a python-ish way to solve it (using not built-in libraries is not allowed). My best attempts lead to something like this:

from ctypes import Union, c_uint32, c_float

class conversion(Union):
    _fields_ = [("int", c_uint32),
                ("float", c_float)]

v = conversion()
v.float = float(input())
print(hex(v.int)[2:])

which is basically C code.

So, is there more "python" way to do this? Did recent python versions introduce something that could be useful for this case?

Solution

Firstly, your implementation is inaccurate because float in CPython implementation is a double precision floating-point type (c++ double) so it's size is 64 bit. You have to use c_uint64 and c_double for best results

You can use the struct module to pack float to Python bytes object and then unpack it to integer value:

import struct
float_to_hex = lambda f: hex(struct.unpack('@Q', struct.pack('@d', f))[0])
print(float_to_hex(123.45)) # Output: 0x405edccccccccccd

"Python" way: you can just use the float.hex() method but the result will be different:

print(123.45.hex()) # Output: 0x1.edccccccccccdp+6