import re


def remove_urls(text):
    """
    Removes twitter short URLS from a string and returns the result.
    URLs are matched by the substring 'https://t.co'. If the string
    contains no matching URLs, the returned string is identical to
    the input string.
    """
    text = re.sub(r"https://t.co\S+", "", text)
    return re.sub(r"\s+", " ", text)