from typing import Optional

from datetime import datetime

def convert_timestamp_string_to_epoch(timestamp: str) -> Optional[int]:
    epoch_time = None
    time_obj = datetime.strptime(timestamp, "%Y-%m-%d %H:%M:%S.%f")
    epoch_time = int((time_obj - datetime(1970, 1, 1)).total_seconds() * 1000)
    return epoch_time


print(int(convert_timestamp_string_to_epoch("2025-08-01 13:11:47.171")))
#above outputs 1754053907171.0

#how to I remove the .0 ?

# Input for row and column
R = int(input())
C = int(input())

# Using list comprehension for input
matrix = [[int(input()) for x in range (C)] for y in range(R)]

x[cat_var].isnull().sum().sort_values(ascending=False)

import itertools

def compute_permutations(string):
    # Generate all permutations of the string
    permutations = itertools.permutations(string)

    # Convert each permutation tuple to a string
    permutations = [''.join(permutation) for permutation in permutations]

    return permutations

# Prompt the user for a string
string = input("Enter a string: ")

# Compute permutations
permutations = compute_permutations(string)

# Display the permutations
print("Permutations:")
for permutation in permutations:
    print(permutation)

print('hello, world')