"fastcore: An Underrated Python Library"¶

A unique python library that extends the python programming language and provides utilities that enhance productivity.

author: "Hamel Husain"
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image: images/copied_from_nb/fastcore_imgs/td.png
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categories: [fastcore, fastai]
permalink: /fastcore/
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#hide
! pip install -U git+git://github.com/fastai/fastcore@master
! pip install -U git+git://github.com/fastai/nbdev@master
! pip install -U numpy
from fastcore.foundation import *
from fastcore.meta import *
from fastcore.utils import *
from fastcore.test import *
from nbdev.showdoc import *
from fastcore.dispatch import typedispatch
from functools import partial
import numpy as np
import inspect

Collecting git+git://github.com/fastai/fastcore@master
  Cloning git://github.com/fastai/fastcore (to revision master) to /private/var/folders/88/9mddczp92wg04x0ykmw940q00000gn/T/pip-req-build-fph52w2h
  Running command git clone -q git://github.com/fastai/fastcore /private/var/folders/88/9mddczp92wg04x0ykmw940q00000gn/T/pip-req-build-fph52w2h
Requirement already satisfied, skipping upgrade: pip in /Users/hamelsmu/anaconda3/lib/python3.8/site-packages (from fastcore==1.0.12) (20.1.1)
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Building wheels for collected packages: fastcore
  Building wheel for fastcore (setup.py) ... done
  Created wheel for fastcore: filename=fastcore-1.0.12-py3-none-any.whl size=40633 sha256=8275b4eaa351c9c867e9c1f83105bc6ec25f251caf1efcf247a8e9ecc0f16f76
  Stored in directory: /private/var/folders/88/9mddczp92wg04x0ykmw940q00000gn/T/pip-ephem-wheel-cache-x8fbj38b/wheels/9b/c8/80/1e03649fe9e96f2b8231a1f38d4e20389036c7cb204afd8563
Successfully built fastcore
Installing collected packages: fastcore
  Attempting uninstall: fastcore
    Found existing installation: fastcore 1.0.12
    Uninstalling fastcore-1.0.12:
      Successfully uninstalled fastcore-1.0.12
Successfully installed fastcore-1.0.12
Collecting git+git://github.com/fastai/nbdev@master
  Cloning git://github.com/fastai/nbdev (to revision master) to /private/var/folders/88/9mddczp92wg04x0ykmw940q00000gn/T/pip-req-build-whf785xv
  Running command git clone -q git://github.com/fastai/nbdev /private/var/folders/88/9mddczp92wg04x0ykmw940q00000gn/T/pip-req-build-whf785xv
Requirement already satisfied, skipping upgrade: pip in /Users/hamelsmu/anaconda3/lib/python3.8/site-packages (from nbdev==1.0.19) (20.1.1)
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Requirement already satisfied, skipping upgrade: backcall in /Users/hamelsmu/anaconda3/lib/python3.8/site-packages (from ipython>=5.0.0->ipykernel->nbdev==1.0.19) (0.2.0)
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Building wheels for collected packages: nbdev
  Building wheel for nbdev (setup.py) ... done
  Created wheel for nbdev: filename=nbdev-1.0.19-py3-none-any.whl size=51832 sha256=69a997325e38de84de9410724f59a24deeab6514bc4bea80bdfc90d12acfcff8
  Stored in directory: /private/var/folders/88/9mddczp92wg04x0ykmw940q00000gn/T/pip-ephem-wheel-cache-r2gv8q50/wheels/28/83/ee/f8ff336622886142e3bc00cfc9ba627f277f30f2ad3d7030f0
Successfully built nbdev
Installing collected packages: nbdev
  Attempting uninstall: nbdev
    Found existing installation: nbdev 1.0.19
    Uninstalling nbdev-1.0.19:
      Successfully uninstalled nbdev-1.0.19
Successfully installed nbdev-1.0.19
Collecting numpy
  Downloading numpy-1.19.2-cp38-cp38-macosx_10_9_x86_64.whl (15.3 MB)
     |████████████████████████████████| 15.3 MB 4.7 MB/s eta 0:00:01
Installing collected packages: numpy
  Attempting uninstall: numpy
    Found existing installation: numpy 1.18.5
    Uninstalling numpy-1.18.5:
      Successfully uninstalled numpy-1.18.5
Successfully installed numpy-1.19.2

There are many more ways of customizing and using store_attr than I highlighted here. Check out the docs for more detail.

P.S. you might be thinking that Python dataclasses also allow you to avoid this boilerplate. While true in some cases, store_attr is more flexible.{% fn 1 %}

{{ "For example, store_attr does not rely on inheritance, which means you won't get stuck using multiple inheritance when using this with your own classes. Also, unlike dataclasses, store_attr does not require python 3.7 or higher. Furthermore, you can use store_attr anytime in the object lifecycle, and in any location in your class to customize the behavior of how and when variables are stored." | fndetail: 1 }}