def expand_qgrams(text, qsize, output):
    """Expands a text into a set of q-grams

    :param text: Text
    :type text: str
    :param qsize: q-gram size
    :type qsize: int
    :param output: output
    :type output: list

    :returns: output
    :rtype: list

    Example:

    >>> from microtc.textmodel import expand_qgrams
    >>> output = list()
    >>> expand_qgrams("Good morning.", 3, output)
    ['q:Goo', 'q:ood', 'q:od ', 'q:d m', 'q: mo', 'q:mor', 'q:orn', 'q:rni', 'q:nin', 'q:ing', 'q:ng.']
    """

    _ = ["".join(a) for a in zip(*[text[i:] for i in range(qsize)])]
    [output.append("q:" + x) for x in _]
    return output