Use a == b to check whether two Python values compare equal. Unlike is, which checks whether two references point to the same object, == uses the values’ equality behavior.
Use == for value comparison
For ordinary comparisons, write a == b:
if a == b:
print("values compare equal")The result depends on the objects’ types and their equality implementation. It does not promise a universal, recursive definition of “same value” for every possible Python object.
How == differs from is
| Operator | Question answered | Typical use |
|---|---|---|
== |
Do these objects compare equal according to their types’ equality behavior? | Comparing values or contents |
is |
Are these references to the very same object? | Checking None or a deliberate sentinel |
For example, two lists can have equal contents while remaining separate objects:
[1, 2] == [1, 2] # True
[1, 2] is [1, 2] # FalsePython’s Data Model reference describes is as comparing object identity. Equality, by contrast, can be customized by a type’s __eq__ method.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
When identity checks are appropriate
Check for None
Use is when checking the None singleton:
if result is None:
handle_missing_result()PEP 8 recommends identity comparisons for singletons. Avoid result == None; equality can be customized, while the identity check directly asks whether the value is the None object.
Check a deliberately created sentinel
A private sentinel distinguishes a missing value from ordinary values, including None:
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
_MISSING = object()
value = lookup(key, default=_MISSING)
if value is _MISSING:
handle_missing_key()Identity is suitable here because the sentinel is intentionally one unique object.
What equality means for different types
Built-in containers
Built-in sequences such as lists and tuples compare equal when they have the same type and length and corresponding elements compare equal. Consequently, a list and tuple with matching items are not equal. Dictionaries compare their key-value pairs.
Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Numbers
Built-in numeric types can compare equal across types when their values are mathematically equal, subject to Python’s numeric comparison rules. Do not assume every pair of different types must compare unequal.
Custom classes
If instances of a class have a meaningful value-based equality, implement __eq__. Python uses rich comparison for x == y. A method can return NotImplemented when it does not support the other operand; if neither side handles the comparison, equality falls back to identity.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
An equality method may return something other than a Boolean. In a conditional such as if x == y:, Python converts the result to truth using bool(). When you define equality for a hashable class, equal objects must have equal hashes. For mutable objects, avoid a hash value that can change while the object is being used as a dictionary key or set member.
Important equality edge cases
NaN is unequal to itself
A floating-point NaN compares unequal to itself: nan == nan is false, even when both operands refer to the same NaN object. Do not use self-equality as a general NaN detection method.
The Tool Desk
Outbyte PC Repair FREEClear out junk files and repair common Windows errorsFree Scan →Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Do not use is for ordinary strings or numbers
Python does not guarantee that equal integer or string values share an object. Identity checks for such constants can appear to work in one situation and fail in another; use == to compare their values.
Quick Recap
Practical rule
- Use
==to compare ordinary values and container contents. - Use
iswhen object identity itself matters, especially forNoneand unique sentinels. - For custom objects, check what their equality method defines rather than assuming equality always means identical contents.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
