if-else inside for loop not working in python

I am writing a simple python script with if-else condition in a for loop by reading inputs line by line from a text file. Below is my script. I should get expected output. Please help! My env.txt contains: DEV01 DEV02 UAT01 UAT02

with open("env.txt") as envnames:
    for eachenv in envnames:
        if eachenv=="DEV01" or "DEV02":
            eachenv="dev"
            print (eachenv)
        elif eachenv=="UAT01" or "UAT02":
            eachenv="uat"
            print(eachenv)
        else :
            print('')

Expected: dev dev uat uat

actual: dev dev dev dev