How can I get a list of locally installed Python modules?

Question

I would like to get a list of Python modules, which are in my Python installation (UNIX server).

How can you get a list of Python modules installed in your computer?

Answer 1

I needed to find the specific version of packages available by default in AWS Lambda. I did so with a mashup of ideas from this page. I'm sharing it for posterity.

import pkgutil

__version__ = '0.1.1'

def get_ver(name):
    try:
        return str(__import__(name).__version__)
    except:
        return None

def lambda_handler(event, context):
    return {
        'statusCode': 200,
        'body': [{
                   'path': m.module_finder.path,
                   'name': m.name,
                   'version': get_ver(m.name),
                 } for m in list(pkgutil.iter_modules())
                 #if m.module_finder.path == "/var/runtime" # Uncomment this if you only care about a certain path
                ],
    }

What I discovered is that the provided boto3 library was way out of date and it wasn't my fault that my code was failing. I just needed to add boto3 and botocore to my project. But without this I would have been banging my head thinking my code was bad.

{
  "statusCode": 200,
  "body": [
    {
      "path": "/var/task",
      "name": "lambda_function",
      "version": "0.1.1"
    },
    {
      "path": "/var/runtime",
      "name": "bootstrap",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "boto3",
      "version": "1.9.42"
    },
    {
      "path": "/var/runtime",
      "name": "botocore",
      "version": "1.12.42"
    },
    {
      "path": "/var/runtime",
      "name": "dateutil",
      "version": "2.7.5"
    },
    {
      "path": "/var/runtime",
      "name": "docutils",
      "version": "0.14"
    },
    {
      "path": "/var/runtime",
      "name": "jmespath",
      "version": "0.9.3"
    },
    {
      "path": "/var/runtime",
      "name": "lambda_runtime_client",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "lambda_runtime_exception",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "lambda_runtime_marshaller",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "s3transfer",
      "version": "0.1.13"
    },
    {
      "path": "/var/runtime",
      "name": "six",
      "version": "1.11.0"
    },
    {
      "path": "/var/runtime",
      "name": "test_bootstrap",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "test_lambda_runtime_client",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "test_lambda_runtime_marshaller",
      "version": null
    },
    {
      "path": "/var/runtime",
      "name": "urllib3",
      "version": "1.24.1"
    },
    {
      "path": "/var/lang/lib/python3.7",
      "name": "__future__",
      "version": null
    },
...

What I discovered was also different from what they officially publish. At the time of writing this:

• Operating system – Amazon Linux
• AMI – amzn-ami-hvm-2017.03.1.20170812-x86_64-gp2
• Linux kernel – 4.14.77-70.59.amzn1.x86_64
• AWS SDK for JavaScript – 2.290.0\
• SDK for Python (Boto 3) – 3-1.7.74 botocore-1.10.74