import re


def is_256b_hex_str(value):
    """
    Checks if a given value is a 32-byte hex encoded string.

    Args:
        value(:mod:`str`): the value to be checked.

    Returns:
        :obj:`bool`: Whether or not the value matches the format.
    """
    return isinstance(value, str) and re.match(r"^[0-9A-Fa-f]{64}$", value) is not None