"""Recommends a timing profile based on the given confidence level.

The function categorizes the confidence level into one of four timing profiles:
- 'stealth' for confidence levels of 0.8 or higher.
- 'conservative' for confidence levels between 0.5 and 0.8.
- 'normal' for confidence levels between 0.2 and 0.5.
- 'aggressive' for confidence levels below 0.2.

Args:
    confidence (float): A confidence level between 0.0 and 1.0, inclusive.

Returns:
    str: The recommended timing profile based on the confidence level. Possible values are 'stealth', 'conservative', 'normal', or 'aggressive'.
"""
You should write code starting with:
def _recommend_timing_profile(confidence: float) -> str:
    pass

