import os
import sys
import csv

AMplateNum = input("Please Scan AM-DNA plate barcode AM******-DNA: ")
NormFileName = AMplateNum + ".txt"
FileToChange = "E:\NormalizeData\" + NormFileName
#this prompts user to scan in AM barcode then builds the file path

def check_value_to_edit(value):
    if float(value) > 353.7000:
        value = "353.7000"
    return value
    else:
    return value
#check_value_to_edit evaluates a "value" as a float and changes it to 353.7
#if the value exceeds it
def get_destination_dictwriter(file):
    with open(FileToChange, 'r') as source:
        csv_source = csv.DictReader(source, delimiter='t')
        fieldnames = csv_source.fieldnames
        dictwriter = csv.DictWriter(file, fieldnames=fieldnames)
        return dictwriter

destination = open(FileToChange, 'w', newline='')
csv_destination = get_destination_dictwriter(destination)

with open(FileToChange, 'r') as source:
        csv_source = csv.DictReader(source, delimiter='t')
        for row in csv_source:
            row["Concentration"] = check_value_to_edit(row)
            csv_destination.writerow(row)


destination.close()