Python Developer for MIME Email Handling

I am in need of a Python developer who is well-versed in handling MIME email content. Your primary task will be to parse the email content that comes through a POST API. This needs to be done in a way that ensures the email body is kept intact.

Key Requirements:
- Proficiency in Python with a focus on email and MIME message handling
- Experience in parsing email content .
- Ability to digest emails coming through a POST API
- Skill in managing email content
- Ensuring the integrity of the email body is maintained

The following additional requirements are also essential:
- Redirecting parsed emails with exact email body with some content adjustments based on placeholders.
- Storing the parsed email content in MIME format
- Script should be able to construct a new email with the MIME message with new sender/recipient addresses.

Ideal candidates for this project will have a strong understanding of email protocols, a demonstrated track record in Python development, and a comprehensive understanding of MIME messages. You should also be comfortable working with APIs and have the ability to maintain the integrity of the email body throughout the process.

I can provide the the Sendgrid API to send POST messages to your testing server (preferably Flask)
I can share some sample data or code if needed.