'Write a comment to a worksheet cell.
Args:
row:     The cell row (zero indexed).
col:     The cell column (zero indexed).
comment: Cell comment. Str.
options: Comment formatting options.
Returns:
0:  Success.
-1: Row or column is out of worksheet bounds.
-2: String longer than 32k characters.'

@convert_cell_args
def write_comment(self, row, col, comment, options=None):

    if (options is None):
        options = {}
    if self._check_dimensions(row, col):
        return (-1)
    if (len(comment) > self.xls_strmax):
        return (-2)
    self.has_vml = 1
    self.has_comments = 1
    self.comments[row][col] = self._comment_params(row, col, comment, options)
