User question:
user: I'm in the middle of analyzing demographic data for a project and need to cross-reference some information based on zip codes. I've got a specific zip code, let's say 90210, and I need to find out which city it corresponds to. Can you help me retrieve the city name for this zip code?

Available functions:
name: calculate_future_value
description: Calculates the future value of an investment.
parameters: type: dict
properties: present_value: type: float
description: The present value of the investment, in dollars.
interest_rate: type: float
description: The interest rate of the investment, ranging from 0 to 1.
periods: type: integer
description: The number of periods, in years.
required: present_value
interest_rate
periods
name: retrieve_city_based_on_zipcode
description: Finds the city of a zipcode.
parameters: type: dict
properties: zipcode: type: string
description: The zipcode of the city.
required: zipcode
name: estimate_derivative
description: Estimate the derivative of a function at a given point.
parameters: type: dict
properties: function: type: string
description: The function to calculate the derivative of.
x: type: integer
description: The point to calculate the derivative at.
required: function
x
name: get_price_by_amazon_ASIN
description: Finds the price of a product by its Amazon ASIN.
parameters: type: dict
properties: ASIN: type: string
description: The Amazon ASIN of the product.
required: ASIN

Ground-truth function call(s):
retrieve_city_based_on_zipcode(zipcode='90210')