server.py

from flask import Flask, render_template, url_for, request, redirect
import csv


app = Flask(__name__)

@app.route('/')
def my_home():
	return render_template('index.html')

@app.route('/<string:page_name>')
def html_page(page_name):
    return render_template(page_name)

def write_to_file(data):
	with open('database.txt', mode='a') as database:
		email = data['email']
		subject = data['subject']
		message = data['message']
		file = database.write('\n {}, {}, {}'.format(email, subject, message))

def write_to_csv(data):		
	with open('database.csv', newline='', mode='a') as database2:
		email = data['email']
		subject = data['subject']
		message = data['message']
		csv_writer = csv.writer(database2, delimiter= ',', quotechar='"', quoting=csv.QUOTE_MINIMAL)
		csv_writer.writerow([email, subject, message])

@app.route('/submit_form', methods=['POST', 'GET'])
def submit_form():
	if request.method == 'POST':
		try:
			data = request.form.to_dict()
			write_to_csv(data)
			return redirect('/thankyou.html')
		except:
			return 'Did not save to database'
	else:
		return 'Somethin went wrong.  Try again!'