def mapa=['Lodz':737000 , 'Warszawa':172000 , 'Krakow':756000]
mapa.each {
println it.key
}
ZGVmIG1hcGE9WydMb2R6Jzo3MzcwMDAgLCAnV2Fyc3phd2EnOjE3MjAwMCAsICdLcmFrb3cnOjc1NjAwMF0KYXNzZXJ0IG1hcGEuTG9keiA9PSA3MzcwMDAKbWFwYS5lYWNoIHsKCgpwcmludGxuIGl0LmtleQp9CgoKCg==