<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def columnConfidences(self, cellConfidences=None):
 """ Compute the column confidences given the cell confidences. If None is passed in for cellConfidences, it uses the stored cell confidences from the last compute. Parameters: cellConfidencs : cell confidences to use, or None to use the the current cell confidences. retval: : Column confidence scores. """


    if cellConfidences is None:
      cellConfidences = self.confidence['t']

    colConfidences = cellConfidences.sum(axis=1)

    # Make the max column confidence 1.0
    #colConfidences /= colConfidences.max()

    return colConfidences