AttributeError: xlColumnClustered

My Python code to generate charts from pywin32 in Excel is:

def add_chart1(location, sheet, range1, title, left, right, height, width, charttype):
    pythoncom.CoInitialize()
    xl = win32.gencache.EnsureDispatch('Excel.Application')
    xl.Visible = True
    ss = xl.Workbooks.Open("demo.xlsx")
    worksheet = ss.Worksheets.Item(sheet)
    workchart = worksheet.ChartObjects().Add(left, right, height, width).Activate()
    xl.ActiveChart.ChartType = charttype
    xl.ActiveChart.Axes(c.xlValue).HasMajorGridlines = False
    xl.ActiveChart.Axes(c.xlCategory).HasTitle = True 
    xl.ActiveChart.SetSourceData(Source=worksheet.Range(range1))
    #workchart.ChartType = 57 # 3DPie
    xl.ActiveChart.HasTitle = True
    workchart_title = xl.ActiveChart.ChartTitle
    workchart_title.Text = title
    
    xl.ActiveChart.HasLegend = True
    xl.ActiveChart.Legend.LegendEntries(1)
    xl.ActiveChart.Legend.Position = -4107 # Right Position
    
    ss.SaveAs("demo.xlsx")
    ss.Close(False); workbook=None
    xl.Application.Quit()

I'm executing this in a flask application. The function call is:

import win32com.client as win32
from win32com.client import constants as c
import pythoncom
from flask import *

app = Flask(__name__)

@app.route('/', methods = ['POST'])
def index():
    add_chart1('demo.xlsx', 'Chart',range1, 'Visualization', 350, 32, 600, 300, c.xlColumnClustered)

The output is:

File "C:\Anaconda3\Lib\site-packages\win32com\client\__init__.py", line 178, in __getattr__
raise AttributeError(a)
AttributeError: xlColumnClustered

As seen in other questions of SO, I cleared the cache in temp\1\gen_py directory but still the error persists.

I tried every solution of this question .

But none of them worked.

Sometimes, the xlChartType enum won't get loaded in the 1st instance. In such cases, give the chart number i.e value instead of names. for xlColumnClustered, it's 51

You can find the values here