utde 0.1.4

A collection of python decorators I wish existed before

utde

A collection of utility decorators to simplify my life.

Persist

Instead of recomputing an expensive function annotate it with a generic_persist decorator. This decorator allows you to specify:

- key_or_fn: Either a string or a function
that generates a string from the wrapped_fn args
- load_fn: A function that is used to retrieve
stored data from key
- store_fn: A function that is used to store
the results of the "expensive" function call so that
it can be loaded next time instead

Example:

from utde import generic_persist

cache = dict()

def key_fn(day_str):
    year, month, day = day_str.split("-")
    return f"{year}/{month}/{day}"

def load_fn(key):
    if key in cache:
        return cache[key]

def store_fn(x, key):
    cache[key] = x

@generic_persist(key_fn, load_fn, store_fn)
def wrapped_fn(x, day_str):
    print("Imagine an expensive operation")
    return x * 2

Pandas (optional)

pip install utde[pandas]

There is a overloaded version for pandas that will load/store using the pickle format. Then you only have to provide where to load/store the file from/to.

WARNING: Only provide a key to a location you trust in, as unpickling a pickle file may execute arbitrary code.

import pandas as pd
from utde import persist_pd

@persist_pd(lambda year: f"yearly_report_{year}.pkl")
def yearly_report(year: str) -> pd.DataFrame:
    return pd.DataFrame(data={"year": [year], "profit": [42]})

Timer

Although its a simple function to write I often reinvented the wheel and wrote a function/decorator to track the execution time of a function of interest.

from utde import timer
import time

@timer
def slow_fn():
    time.sleep(2)

slow_fn()

Output:

INFO: `slow_fn` ellapsed time: 2.000s