I use this gist to parse large xlsx file to get the inserts for my database

xlsx_to_insert.py

import xlrd
from tkinter import filedialog
from tkinter import Tk
import os

Tk().withdraw() # we don't want a full GUI, so keep the root window from appearing
print("Start .xlsx parser")
path = filedialog.askopenfilename(initialdir = os.getcwd(),title = "Select an spreedsheet to parse ",filetypes = (("Excel files","*.xlsx"),("all files","*.*"))) # show an "Open" dialog box and return the path to the selected file

print("Opening file: " + path)
workbook = xlrd.open_workbook(path)
print("File loaded successfully")
sheet_names = workbook.sheet_names()
print('Sheet Names: ', sheet_names)

selectedSheet = input("Select the sheet you want to parse: " + ' '.join(sheet_names) + "\n")
print('Parsing sheet: ', selectedSheet)
sheet = workbook.sheet_by_name(selectedSheet)

resultFileName = filedialog.askopenfilename(initialdir = os.getcwd(),title = "Where you want the result sql?",filetypes = (("Sql files","*.sql *.txt"),("all files","*.*")))
print("Generating result file: " + resultFileName)
file = open(resultFileName,'w')
# Create a For loop to iterate through each row in the XLS file, starting at row 2 to skip the headers
for r in range(1, sheet.nrows):
	#I know which cell represent each variable, so...
	id = str(int(sheet.cell(r,0).value))
	id_event = str(int(sheet.cell(r,1).value))
	description	= str(sheet.cell(r,2).value)

    # Generate each insert
	file.write("INSERT INTO DTV_CROSS_EVENT_REASON (ID, ID_EVENT, DESCRIPTION) values (" + id + ", " + id_event + ", '" + description + "');\n")

file.close()
print("Finish .xlsx parser")