<SYSTEM_TASK:>
Given the following text description, write Python code to implement the functionality described below step by step
<END_TASK>
<USER_TASK:>
Description:
 Translating between Currencies
Step1:  Translating between currencies requires a number of different choices
do you want to consider the relative value of two currencies based on Market Exchange Rates or Purchasing Power Parity?
do you subscribe to the the GDP Deflator or Consumer Price Index schools of inflation calculations?
Which to use can be very context or use case dependent. salamanca offers all options with data supplied by the World Bank. Below are a few examples.
Basics
Let's start by getting to know the trusty Translator and its primary weapon exchange()
Step2:  Every translation is based on countries and years. By default, the Translator assumes you want the USD value of a currency in a year based on market exchange rates using GDP deflators.
So, for example, translating 20 Euros (the currency of Austria) in 2010 would net you 26.5 US Dollars.
Step3:  You can further translate 20 2010 Euros into 2015 US Dollars as
Step4:  Additional Options
You can specify options such as using CPI rather than GDP Deflators
Step5:  Similarly, you can use Purchasing Power Parity rather than Market Exchange Rates
<ASSISTANT_TASK:>
Python Code:
from salamanca.currency import Translator
Explanation: Translating between Currencies
End of explanation
xltr = Translator()
Explanation: Translating between currencies requires a number of different choices
do you want to consider the relative value of two currencies based on Market Exchange Rates or Purchasing Power Parity?
do you subscribe to the the GDP Deflator or Consumer Price Index schools of inflation calculations?
Which to use can be very context or use case dependent. salamanca offers all options with data supplied by the World Bank. Below are a few examples.
Basics
Let's start by getting to know the trusty Translator and its primary weapon exchange()
End of explanation
xltr.exchange(20, iso='AUT', yr=2010)
xltr.exchange(20, fromiso='AUT', toiso='USA', yr=2010) # equivalent to the above defaults
Explanation: Every translation is based on countries and years. By default, the Translator assumes you want the USD value of a currency in a year based on market exchange rates using GDP deflators.
So, for example, translating 20 Euros (the currency of Austria) in 2010 would net you 26.5 US Dollars.
End of explanation
xltr.exchange(20, fromiso='AUT', toiso='USA', 
              fromyr=2010, toyr=2015)
Explanation: You can further translate 20 2010 Euros into 2015 US Dollars as
End of explanation
xltr.exchange(20, fromiso='AUT', toiso='USA', 
              fromyr=2010, toyr=2015, 
              inflation_method='cpi')
Explanation: Additional Options
You can specify options such as using CPI rather than GDP Deflators
End of explanation
xltr.exchange(20, fromiso='AUT', toiso='USA', 
              fromyr=2010, toyr=2015, 
              units='PPP')
Explanation: Similarly, you can use Purchasing Power Parity rather than Market Exchange Rates
End of explanation
<END_TASK>