Set to string. Obvious: String to set? Maybe like this? Extremely ugly. Is there better way to serialize/deserialize sets? Answer Use repr and eval: Note that eval is not safe if the source of string is unknown, prefer ast.literal_eval for safer conversion: help on repr:
Tag: set
Use curly braces to initialize a Set in Python
I’m learning python, and I have a novice question about initializing sets. Through testing, I’ve discovered that a set can be initialized like so: Are there any disadvantages of doing it this way, as opposed to the standard way of: or is it just a question of style? Answer There are two obvious issues with the set literal syntax: It’s
How to JSON serialize sets?
I have a Python set that contains objects with __hash__ and __eq__ methods in order to make certain no duplicates are included in the collection. I need to json encode this result set, but passing even an empty set to the json.dumps method raises a TypeError. I know I can create an extension to the json.JSONEncoder class that has a
Get difference between two lists with Unique Entries
I have two lists in Python: Assuming the elements in each list are unique, I want to create a third list with items from the first list which are not in the second list: Are there any fast ways without cycles and checking? Answer To get elements which are in temp1 but not in temp2 (assuming uniqueness of the elements in
How to retrieve an element from a set without removing it?
Suppose the following: How do I get a value (any value) out of s without doing s.pop()? I want to leave the item in the set until I am sure I can remove it – something I can only be sure of after an asynchronous call to another host. Quick and dirty: But do you know of a better way?