how to declare variable type, C style in python

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I'm a programming student and my teacher is starting with C to teach us the programming paradigms, he said it's ok if I deliver my homework in python (it's easier and faster for the homeworks). And I would like to have my code to be as close as possible as in plain C.
Question is:
How do I declare data types for variables in python like you do in C. ex:

int X,Y,Z;

I know I can do this in python:

x = 0
y = 0
z = 0

But that seems a lot of work and it misses the point of python being easier/faster than C. So, whats the shortest way to do this?
P.S. I know you don't have to declare the data type in python most of the time, but still I would like to do it so my code looks as much possible like classmates'.

c python variables
8 Answers

Starting with Python 3.6, you can declare types of variables and funtions, like this :

explicit_number: type

or for a function

def function(explicit_number: type) -> type:
    pass

This example from this post: How to Use Static Type Checking in Python 3.6 is more explicit

from typing import Dict

def get_first_name(full_name: str) -> str:
    return full_name.split(" ")[0]

fallback_name: Dict[str, str] = {
    "first_name": "UserFirstName",
    "last_name": "UserLastName"
}

raw_name: str = input("Please enter your name: ")
first_name: str = get_first_name(raw_name)

# If the user didn't type anything in, use the fallback name
if not first_name:
    first_name = get_first_name(fallback_name)

print(f"Hi, {first_name}!")

See the docs for the typing module

user_73910920

Simply said: Typing in python is useful for hinting only.

x: int = 0
y: int = 0 
z: int = 0
user_62526310

I'm surprised no one has pointed out that you actually can do this:

decimalTwenty = float(20)

In a lot of cases it is meaningless to type a variable, as it can be retyped at any time. However in the above example it could be useful. There are other type functions like this such as: int(), long(), float() and complex()

user_64208150

I use data types to assert unique values in python 2 and 3. Otherwise I cant make them work like a str or int types. However if you need to check a value that can have any type except a specific one, then they are mighty useful and make code read better.

Inherit object will make a type in python.

class unset(object):
    pass
>>> print type(unset)
<type 'type'>

Example Use: you might want to conditionally filter or print a value using a condition or a function handler so using a type as a default value will be useful.

from __future__ import print_function # make python2/3 compatible
class unset(object):
    pass


def some_func(a,b, show_if=unset):
    result = a + b
    
    ## just return it
    if show_if is unset:
        return result
    
    ## handle show_if to conditionally output something
    if hasattr(show_if,'__call__'):
        if show_if(result):
            print( "show_if %s = %s" % ( show_if.__name__ , result ))
    elif show_if:
        print(show_if, " condition met ", result)
        
    return result
    
print("Are > 5)")
for i in range(10):
    result = some_func(i,2, show_if= i>5 )
    
def is_even(val):
    return not val % 2


print("Are even")
for i in range(10):
    result = some_func(i,2, show_if= is_even )

Output

Are > 5)
True  condition met  8
True  condition met  9
True  condition met  10
True  condition met  11
Are even
show_if is_even = 2
show_if is_even = 4
show_if is_even = 6
show_if is_even = 8
show_if is_even = 10

if show_if=unset is perfect use case for this because its safer and reads well. I have also used them in enums which are not really a thing in python.

user_12239460
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