Monty: Python Made Even Easier

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Monty is the missing complement to Python. Monty implements supplementary useful functions for Python that are not part of the standard library. Examples include useful utilities like transparent support for zipped files, useful design patterns such as singleton and cached_class, and many more.

Python is a great programming language and comes with “batteries included”. However, even Python has missing functionality and/or quirks that make it more difficult to do many simple tasks. In the process of creating several large scientific frameworks based on Python, my co-developers and I have found that it is often useful to create reusable utility functions to supplement the Python standard library. Our forays in various developer sites and forums also found that many developers are looking for solutions to the same problems.

Monty is created to serve as a complement to the Python standard library. It provides suite of tools to solve many common problems, and hopefully, be a resource to collect the best solutions.

Monty supports Python 2.7-3.x.

Change Log

v1.0.2

  1. Misc bug fixes (tempdir on Windows)

v1.0.1

  1. Use CLoader and CDumper by default for speed.

v1.0.0

  1. Ruamel.yaml is now used as the default YAML parser and dumper.

Older versions

Installation

Standard pip install:

pip install monty

Usage

Unlike most other modules, the organization of Monty mirrors that of the standard Python library where possible. This style is adopted so that that it is almost always obvious where a particular method or function will reside. There are two recommended ways of using Monty.

Method 1: Import the monty root:

import monty as mty
with mty.io.zopen("src.gz") as f:
    data = f.read()
with mty.io.zopen("dest.bz2", "wb") as f:
    f.write(data)

Method 2: Import specific functions as needed:

from monty.io import zopen
with zopen("file.gz") as f:
    data = f.read()
with zopen("dest.bz2", "wb") as f:
    f.write(data)

The above is an example of how Monty supplements the standard Python library. The standard library contains functions for dealing with gzipped and bzip2 files. What Monty adds is a layer of abstraction that allows the type of compression (or no compression) to be determined from the filename and the appropriate standard library function is chosen to open the files. All the typical args and kwargs of “open” are supported. The syntax “zopen” mirrors standard Unix’s zless/zgrep commands.

Below are some further examples of Monty’s features:

from monty.design_patterns import singleton, cached_class

# The singleton design pattern

@singleton
class A():
    pass

# Note that cached classes must be new style, i.e. inherits object in
# Python 2.7. A cached class is one which has one unique instance per
# set of args and kwargs.

@cached_class
class B(object):

    def __init__(self, b):
        self.b = b

# Highly efficient of reading of lines from back of file.

from monty.io import zopen, reverse_readline
with zopen("myfile") as f:
    for line in reverse_readline(f):
        print(line)

# A frozen dict (Immutable dict)

from monty.collections import frozendict
d = frozendict(a=1)

# A Fabric-inspired cd context, that allows one to change directory to
# execute code and transparently changes back to the current working
# directory

from monty.os import cd

with cd("/path/to/input_files") as f:
    execute_code_using_files()

Contributing

Contributions to Monty are always welcome. Feel free to visit the Monty Github repo to fork the repo or to submit Issues.

License

Monty is released under the MIT License. The terms of the license are as follows:

The MIT License (MIT)

Copyright (c) 2014 Materials Virtual Lab

Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

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