Demonstrating a global reference variable in action for a friend

help_for_sean.py

import copy
import random

global market_ref
market_ref = {'item_1': 100.0,
              'item_2': 200.0,
              'item_3': 100.0}

def market_shift():
    #updates the global market baseline
    #check out this random walk on Wall St.
    for key in market_ref:
        market_ref[key] += random.uniform(-0.1, 0.1) * market_ref[key]

class Planet
    def __init__(self, params['volatility']):
        #common attributes
        self.market = copy.copy(market_ref)
        self.volatility = params['volatility']
        
        #planet specific attributes
        self.gravity = 2.0 #this could be a base you modify adaptively or a params object
        
    def market_update(self):
        #this permanently modifies the planet market, but not the global reference baseline above
        #planet specific market randomization strategy
        for key in self.market:
          self.market[key] += random.uniform(-self.volatility, self.volatility) * self.market[key]
        
class Space_Station
    def __init__(self, params):
        #common attributes
        self.market = copy.copy(market_ref)
        self.volatility = params['volatility']
        self.name = random.choice(params['names'])
        
        #space station specific attributes
        self.defense_rating = 200 #this could be a base you modify adaptively or a params object
      
    def market_update(self, params)
        #space station specific randomization strategy
        #here I can define a completely different update strategy
        if params['faction'] == "Imperial":
          #double prices
          for key in self.market:
            self.market[key] = 2.0 * self.market[key]
        else:
          #randomize but discount
          for key in self.market:
            self.market[key] += random.uniform(-self.volatility, self.volatility) * self.market[key]
     
        #I could do a higher level abstraction and just define one class as "location" and decide
        #if its a planet or a space station as an attribute, but this demonstrates the purpose of a
        #global variable