"""Flattens and merges multiple iterables by interleaving their elements, removing any `None` values.

Given an iterable of iterables, this function interleaves their elements in a round-robin fashion, 
flattens the result, and removes any `None` values that may have been introduced by uneven lengths.

Args:
    iterable: An iterable of iterables whose elements are to be interleaved and flattened.

Returns:
    A list containing the interleaved and flattened elements from the input iterables, 
    with `None` values removed.
"""
You should write code starting with:
import itertools

def undistribute(iterable) -> list:
    # TODO: Implement this function
    pass

