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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def GetColumnNumber (self, columnName):

 """returns the column number for a given column heading name, 0 if not found"""

                for row in range(1, self.maxRow + 1):
                        for column in range(1, self.maxColumn + 1):
                                if self.GetCellValue(column, row, "") == columnName:
                                        return column
                return 0