[Python] Is there an equivalent of Python's argsort function in DolphinDB?

I'm trying to implement the following functionality in DolphinDB:

Create a dictionary with city names as keys and population counts as values

Find cities with population over 10 million

Sort cities by population in descending order

In Python, this can be easily achieved with:

# Create dictionary
city_population = {"New York": 8419000, "Tokyo": 13960000, "London": 8900000}

# Find cities with population > 10 million
large_cities = {city: pop for city, pop in city_population.items() if pop > 10000000}
print("Cities with population > 10M:", large_cities)

# Sort by population
sorted_cities = dict(sorted(city_population.items(), key=lambda x: x[1], reverse=True))
print("Cities sorted by population:", sorted_cities)`


In DolphinDB, I've attempted:

// 1. Create dictionary
cityDict = dict(["New York", "Tokyo", "London"], [8419000, 13960000, 8900000])

// 2. Find cities with population > 10M
mask = cityDict.values() > 10000000
largeCities = dict(cityDict.keys()[mask], cityDict.values()[mask])
print("Cities with population > 10M: " + string(largeCities))

// 3. Sort by population (descending)
sortedValues = cityDict.values().sort(false) // Get sorted values
sortedKeys = cityDict.keys()[cityDict.values().argsort().reverse()] // Get corresponding sorted keys
sortedDict = dict(sortedKeys, sortedValues)
print("Cities sorted by population: " + sortedDict)


However, I'm getting an error that argsort doesn't exist. How should I properly implement this sorting functionality in DolphinDB?

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