def displace_tokens(tokens, cols):
    """
    Displace all tokens in list which are in the same line as the the first
    token by the given number of columns
    """
    if not tokens or cols == 0:
        return
    lineno = tokens[0].start.lineno
    for token in tokens:
        if token.start.lineno == lineno:
            token.displace(cols)
        else:
            break
