TelegramBot/modules/utils.py

from datetime import datetime
from typing import Union

from pytz import UTC
from pytz import timezone as pytz_timezone


def to_utc(date: datetime, timezone: Union[str, None] = None) -> datetime:
    """Move timezone unaware datetime object to UTC timezone and return it.

    ### Args:
        * date (`datetime`): Datetime to be converted.
        * timezone (`Union[str, None] = None`): Timezone name (must be pytz-compatible). Defaults to `None` (UTC).

    ### Returns:
        * `datetime`: Timezone unaware datetime in UTC with timezone's offset applied to it.
    """
    timezone = "UTC" if timezone is None else timezone
    return pytz_timezone(timezone).localize(date).astimezone(UTC).replace(tzinfo=None)


def from_utc(date: datetime, timezone: Union[str, None] = None) -> datetime:
    """Move timezone unaware datetime object to the timezone specified and return it.

    ### Args:
        * date (`datetime`): Datetime to be converted.
        * timezone (`Union[str, None] = None`): Timezone name (must be pytz-compatible). Defaults to `None` (UTC).

    ### Returns:
        * `datetime`: Timezone unaware datetime in timezone provided with offset from UTC applied to it.
    """
    timezone = "UTC" if timezone is None else timezone
    return (
        pytz_timezone("UTC")
        .localize(date)
        .astimezone(pytz_timezone(timezone))
        .replace(tzinfo=None)
    )