In python how to create multiple dataclasses instances with different objects instance in the fields? Question: I’m trying to write a parser and I’m missing something in the dataclasses usage. I’m trying to be as generic as possible and to do the logic in the parent class but every child has the sames values in …
Error: Object of type IntervalStrategy is not JSON serializable when add `indent` to verticalize json Question: I want to save a dataclass to a json file and save it, it is ok now without adding paramenter indent. class EnhancedJSONEncoder(json.JSONEncoder): def default(self, o): if dataclasses.is_dataclass(o): return dataclasses.asdict(o) # return super().default(o) model_json = json.dumps(model_args, cls=EnhancedJSONEncoder) model_args is …
Dataclasses and slots causing ValueError: 'b' in __slots__ conflicts with class variable Question: I don’t understand the error message and also couldn’t find other SO questions and answers helping me to understand this. The MWE is tested with Python 3.9.2. I’m aware that there is a slots=True parameter in Pythons 3.10 dataclasses. But this isn’t …
Issue with creation of nested data classes Question: I’m trying to create nested data classes: from dataclasses import dataclass, field import datetime from typing import List @dataclass class LineItem: displayName: str compareAtPrice: float discountedPrice: float pricing: str = field(init=False) def __post_init__(self): self.pricing = ( "regular" if self.compareAtPrice == self.discountedPrice else "on sale" ) @dataclass class …
Store an array, or a list, of fixed length as a class attribute using slots in python Question: I have an object that represents a User and a variable measured 20 times. The object will be something like this: class User: user_id: str measures: List[float] #this is a list(or an array) of size 20 Given …
How to subclass a frozen dataclass Question: I have inherited the Customer dataclass. This identifies a customer in the customer DB table. Customer is used to produce summary statistics for transactions pertaining to a given customer. It is hashable, hence frozen. I require a SpecialCustomer (a subclass of Customer) it has an extra property: special_property. …
Can you modify an object's field every time another field is modified? Question: I have a dataclass that looks like this from dataclasses import dataclass, field @dataclass class Data: name: str | None = None file_friendly_name: str | None = field(default=None, init=False) def __post_init__(self): # If name, automatically create the file_friendly_name if self.name: self.file_friendly_name = …
Category and subcategory classes. Need code example Question: I have dict type dataset like [{id, category, parent_id},]. I need create class for parse this dataset and create simple interface to get parents and childrens. I dnt want to invent a wheel, can someone share the code that will help me to implement this task? I …
Python: initiated Logger with dataclass field param Question: This is my Logger class: import logging import os import datetime class Logger: _logger = None def __new__(cls, user: str, *args, **kwargs): if cls._logger is None: cls._logger = super().__new__(cls, *args, **kwargs) cls._logger = logging.getLogger("crumbs") cls._logger.setLevel(logging.DEBUG) formatter = logging.Formatter(‘[%(asctime)s] [%(levelname)s] [%(filename)s] [%(funcName)s] [%(lineno)d]: %(message)s’) now = datetime.datetime.now() directory_name …
create dataclass with optional attribute Question: I’m trying create dataclass with optional attribute is_complete: from dataclasses import dataclass from typing import Optional @dataclass(frozen=True) class MyHistoricCandle: open: float high: float low: float close: float volume: int time: datetime is_complete: Optional[bool] But when i init MyHistoricCandle object without is_complete attribute: MyHistoricCandle(open=1, high=1, low=1, close=1, volume=1, time=datetime.now()) Getting …
