there is a dictionary: geo_data = {'Center': ['Moscow', 'Tula', 'Yaroslavl'], {'Northwest': ['Petersburg', 'Pskov', 'Murmansk'], 'Far East': ['Vladivostok', 'Sakhalin', 'Khabarovsk']} Write a function that will search the strings for the value of the dictionary, and if it exists, it will return the key of the dictionary. For example: geo_class('Pskov') Result: 'Northwest'

geo_data = {'Center': ['Moscow', 'Tula', 'Yaroslavl'], 'Northwest': ['Petersburg', 'Pskov', 'Murmansk'], 'Far East': ['Vladivostok', 'Sakhalin', 'Khabarovsk']}

def geo_class(city):
    for region in geo_data:
        if city in geo_data[region]:
            return region
        
geo_class('Pskov')