Introduce Amazon Comprehend Service

[gopidesupavan]

Added Amazon Comprehend Start Pii Entities Detection Job Operator Doc, Hook,
Operator, Sensor, Trigger, Waiter, Unit Test, System Test.

At present it supports only Pii Entities Detection Job. Remaining Comprehend services coming next.

https://boto3.amazonaws.com/v1/documentation/api/latest/reference/services/comprehend/client/start_pii_entities_detection_job.html

Sample Dag:

from datetime import datetime

from airflow import DAG
from airflow.providers.amazon.aws.operators.comprehend import ComprehendStartPiiEntitiesDetectionJobOperator

with DAG(
    dag_id="comprehend_testing",
    schedule_interval=None,
    start_date=datetime(2021, 1, 1),
    tags=["comprehend pii entities detection"],
    catchup=False,
) as dag:
    pii_entities_detection_job = ComprehendStartPiiEntitiesDetectionJobOperator(
        task_id="pii_entities_detection_job",
        input_data_config={"S3Uri": f"s3://aws-comprehend-testing-hpl7cy/sample_data.txt",
                           "InputFormat": "ONE_DOC_PER_LINE",
                           },
        output_data_config={"S3Uri": f"s3://aws-comprehend-testing-hpl7cy/redacted_output/"},
        mode="ONLY_REDACTION",
        language_code="en",
        data_access_role_arn="arn:aws:iam::{ACCOUNT_ID}:role/ComprehendRole",
        start_pii_entities_kwargs={"RedactionConfig": {"PiiEntityTypes": ["NAME", "ADDRESS"],
                                                       "MaskMode": "REPLACE_WITH_PII_ENTITY_TYPE"}}
    )

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[vincbeck]

Really good job! Thanks for following the good practises and everything. I just added one question but overall it is really good!

[o-nikolas]

This is an awesome PR! Super thorough and ticks all the boxes. We'll use this as an example for future folks, great work! 😃

[gopidesupavan]

This is an awesome PR! Super thorough and ticks all the boxes. We'll use this as an example for future folks, great work! 😃

Thank you so much for reviewing this 😄 , Applied all your feedback.
The quick start guides are really helpful and well documented.

[vincbeck]

Awesome PR!

[gopidesupavan]

Awesome PR!

Thank you @vincbeck 😃