


def sim(input):
    """
    Return 10 most related keywords from kcm result.
    Parameters
    ----------
    input : string
        only keywords on kcm dict will return result, otherwise return empty list
        
    output : two-dimensional list
        The output is a two-dimensional list.
        The output contains 10 elements.
        Each element is a list with two items:
            The first item is related keyword and the second item is frequency.

        Example:
        [ [“高雄市”, 39], [“國民黨”, 39], [“候選人”, 24],……. ]

    """
    pass
