![]() ![]() In the following example, we will see how to use time.ctime() to get the current time as a string. This method takes no arguments, and it returns the current time in the local time zone. Whether you need the local time, UTC time, or a specific time zone, there’s a function or method that can help. The time module in Python provides several methods for getting the current time. ![]() These examples will give you a high-level overview of the methods we will be covering, and we’ll discuss each one in more detail later in the article. Here are some quick examples that we will be discussing in this article. Quick Examples of Python How to Get Current Time Since then, I have come to believe that using naïve datetimes to represent system local time is probably the best compromise available that leaves all the datetime invariants intact without basically redesigning the whole thing from scratch, which I have written up in Why naïve times are local times in Python.1. ![]() When I first wrote this post, I felt that there was no good way to represent local times in Python. For UTC the story is much less complicated. I generally do agree with this, and if you want the "current system time", you can use dateutil.tz.tzlocal to get an aware datetime representing this however, there are edge cases that make defining a clean "local time zone" object less straightforward. You could make the case that datetime.now() and omtimestamp() suffer from the same problem, since "the current time in the system timezone" is just as concrete as "the current time in UTC" is. This may sound like a familiar story to those who have read my earlier post on pytz. So in Python 2, operations like astimezone() will raise an exception when called on a naïve datetime: The change that made utcnow dangerous is that naïve datetimes underwent a subtle shift in meaning: for certain operations that require interpreting a datetime as a fixed point in time, rather than throwing an error they would instead assume that the datetime represents the current system local time zone. With this change, you now have a clear and unambiguous way to mark which of your datetimes are in UTC without bringing in third party code or implementing your own UTC class. The first is that a concrete time zone class, datetime.timezone, was introduced, along with a constant UTC object,. In Python 3, two things have changed that make utcnow unnecessary and, in fact, dangerous. Awareness of the datetime's time zone allows you to do things like arithmetic and comparison between time zones, conversion to other time zones and other operations which require a concrete datetime. By contrast aware datetimes represent a specific point in time in a specific time zone. When originally conceived, naïve datetimes were intended to be abstract, not representing any specific time zone, and it was up to the program to determine what they represent - this is no different from abstract numbers which can represent mass in kilograms, distance in meters or any other specific quantity according to the programmer's intention. Rather than make you stick around for a history lesson as to why this problem exists, I'm going to spoil the ending and say that the right thing to do is to pass a UTC object to the tz parameter of now() and fromtimestamp(), respectively, to get a time zone-aware datetime: ![]() I imagine that these functions would not exist if the datetime library were redesigned today, but at the moment there are a mix of harmful and harmless uses of them out there, and it's not a simple matter to rip them all out. This is due to an unfortunate quirk of history and a subtle shift in what it means for a datetime to be naïve that took place in the Python 2 to 3 transition. When executed with your system locale set to UTC, this will succeed just fine, but when executed in any locale where the offset at that particular timestamp is something other than 0, the assertion fails - for example when executed with an America/New_York locale, you'll get AssertionError: 1571595618.0 != 1571610018.0. From datetime import datetime ts = 1571595618.0 x = datetime. ![]()
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