from typing import List


def ensure_escaped(value: str, *symbols: str) -> str:
    """
    Ensures all instances of a symbol are escaped (via \\) within a value.
    Multiple symbols can be processed at once.
    """
    escaped: str = value
    for symbol in symbols:
        replace_term: str = "\\{}".format(symbol)
        oparts: List[str] = str(escaped).split(replace_term)
        eparts: List[str] = []
        for opart in oparts:
            eparts.append(opart.replace(symbol, replace_term))
        escaped = replace_term.join(eparts)
    return escaped