read and write in excel file with python

I am trying to read the cell of a excel file in python, change its value and save it. If I do not have the line from xlutils.copy import copy in code, it recognizes workbook.sheeets(), but otherwise it says

    AttributeError: 'Workbook' object has no attribute 'sheets'

Here is my code:

    from xlutils.copy import copy

    import xlrd
    st = xlwt.easyxf('pattern: pattern solid;')
    rb = xlrd.open_workbook('00-17.xlsx')

    workbook = copy(rb)
    for sheet in workbook.sheets():
        for row in range(sheet.nrows):

            current_value = sheet.cell(row,3).value
            if(current_value == '1' ) :
                st.pattern.pattern_fore_colour = 5

                for column in [0,2,3]:
                    value = sheet.cell(row, column).value

                    print value
                    sheet.write(row, column, value,st)
    workbook.save('1.xlsx')