import re


def replace_empty_bracket(tokens):
    """
    Remove empty bracket
    :param tokens: List of tokens
    :return: Fixed sequence
    """
    merged = "".join(tokens)
    find = re.search(r"\{\}", merged)
    while find:
        merged = re.sub(r"\{\}", "", merged)
        find = re.search(r"\{\}", merged)
    return list(merged)