Merge branch 'develop' into docs/parser

* develop: (23 commits)
  improv: rename schema to model as per Tom's review
  improv: rename to event_parser as per Tom's review
  Update aws_lambda_powertools/utilities/parser/pydantic.py
  chore: remove flake8 polyfill as explicit dep
  chore: explicit DynamoDB Stream schema naming
  improv: expose all pydantic imports
  improv: adjust high level imports
  improv: add docstrings; event internal param renamed
  improv: propagate exception to parser
  chore: lint
  feat: add standalone parse function
  chore: kwarg over arg to ease refactoring
  fix: code inspect issues
  improv: simplify base envelope; increase test cov
  improv: test parser
  fix: unnecessary return; better error handling
  Update README.md (#190)
  improv: raise own exception; remove duplicates
  fix: snake_case
  improv: envelope structure & import
  ...

Author: heitorlessa

Diff for: README.md

@@ -1,9 +1,9 @@
-# AWS Lambda Powertools
+# AWS Lambda Powertools (Python)
 
 ![Build](https://github.com/awslabs/aws-lambda-powertools/workflows/Powertools%20Python/badge.svg?branch=master)
 ![PythonSupport](https://img.shields.io/static/v1?label=python&message=3.6%20|%203.7|%203.8&color=blue?style=flat-square&logo=python) ![PyPI version](https://badge.fury.io/py/aws-lambda-powertools.svg) ![PyPi monthly downloads](https://img.shields.io/pypi/dm/aws-lambda-powertools)
 
-A suite of utilities for AWS Lambda functions to ease adopting best practices such as tracing, structured logging, custom metrics, and more.
+A suite of Python utilities for AWS Lambda functions to ease adopting best practices such as tracing, structured logging, custom metrics, and more. ([AWS Lambda Powertools Java](https://github.com/awslabs/aws-lambda-powertools-java) is also available).
 
 **[📜Documentation](https://awslabs.github.io/aws-lambda-powertools-python/)** | **[API Docs](https://awslabs.github.io/aws-lambda-powertools-python/api/)** | **[🐍PyPi](https://pypi.org/project/aws-lambda-powertools/)** | **[Feature request](https://github.com/awslabs/aws-lambda-powertools-python/issues/new?assignees=&labels=feature-request%2C+triage&template=feature_request.md&title=)** | **[🐛Bug Report](https://github.com/awslabs/aws-lambda-powertools-python/issues/new?assignees=&labels=bug%2C+triage&template=bug_report.md&title=)** | **[Hello world example](https://github.com/aws-samples/cookiecutter-aws-sam-python)** | **[Detailed blog post](https://aws.amazon.com/blogs/opensource/simplifying-serverless-best-practices-with-lambda-powertools/)**
 

Diff for: aws_lambda_powertools/utilities/advanced_parser/__init__.py

@@ -0,0 +1,17 @@
+"""Advanced event_parser utility
+"""
+from . import envelopes
+from .envelopes import BaseEnvelope
+from .exceptions import ModelValidationError
+from .parser import event_parser
+from .pydantic import BaseModel, root_validator, validator
+
+__all__ = [
+    "event_parser",
+    "envelopes",
+    "BaseEnvelope",
+    "BaseModel",
+    "validator",
+    "root_validator",
+    "ModelValidationError",
+]