Jul 1, 2019 · When you want to collect an immutable ordered list of elements, use a tuple. (For example, when you want a (name, phone_number) pair that you wish to use as an element in a set, you would need a tuple rather than a list since sets require elements be immutable). When you want to collect a mutable ordered list of elements, use a list. (For ...

In Python 3.7, normal dictionaries are ordered, so you don't need to use OrderedDict anymore (but you still can – it's basically the same type). The CPython implementation of Python 3.6 already included that change, but since it's not part of …

Jul 13, 2017 · Dictionaries are the python equivalent of Hash table. It stores values as key-value pairs. Values can be any python objects whereas, keys need to immutable. Below are some of the ways to iterate over a dictionary in python

Here are quite a few ways to add dictionaries. You can use Python3's dictionary unpacking feature: ndic = {**dic0, **dic1} Note that in the case of duplicates, values from later arguments are used. This is also the case for the other examples listed here.

Minor variation to user1850980's answer (for the question "How to initialize a list of empty dictionaries") using list constructor:

Mar 22, 2020 · You've already got it: A if test else B is a valid Python expression. The only problem with your dict comprehension as shown is that the place for an expression in a dict comprehension must have two expressions, separated by a colon:

Then, instead of dict1, use {v: k for k, v in dict1.items()} and instead of dict2 use {v: k for k, v in dict2.items()}. And, if you want the case where it's either the key or the dictionary, then use the union of the intersection given in the answer and the intersection given in this comment. –

Mar 1, 2010 · For example, compare the output of pprint.pprint(person) using this approach, versus what you would have gotten had you used a regular python dict. Admittedly, you could fix that difference by adding a __repr__ method to the my_dict class, but that means you are already no longer using this "Simplest solution" anymore.

@Ben Believe me, I am very aware of that, I have 8 years providing software solutions, this is the first time I use Python and I wish I could use many security features from other languages, however I can not control it, I need to make the module somewhat "Read-Only", the costumer asks us to give them "proofs" that the scripting feature is as ...

I've updated @alexpinho98 answer for Python 3.12 because a lot has changed in the past 11 years. Results. Key Takeaways: Classes in Python 3 are a lot faster now. Use classes instead of dicts where performance is important. TypeDict has no affect on the performance of dicts. Plain dataclasses take twice as long to instantiate.