Dependency inversion

# line 6, CurrencyConverter is subclass of high-level AbatractBaseClass ABC  
# line 16, AlphaConverter is subclass of CurrencyConverter 
# line 32, App is dependent of above high-level class i.e. dependency inversion 
from abc import ABC

class CurrencyConverter(ABC):
    def convert(self, from_currency, to_currency, amount) -> float:
        pass

class FXConverter(CurrencyConverter):
    def convert(self, from_currency, to_currency, amount) -> float:
        print('Converting currency using FX API')
        print(f'{amount} {from_currency} = {amount * 1.2} {to_currency}')
        return amount * 1.15

class AlphaConverter(CurrencyConverter):
    def convert(self, from_currency, to_currency, amount) -> float:
        print('Converting currency using Alpha API')
        print(f'{amount} {from_currency} = {amount * 1.2} {to_currency}')
        return amount * 1.2

class App:
    def __init__(self, converter: CurrencyConverter):
        self.converter = converter

    def start(self):
        self.converter.convert('EUR', 'USD', 100)


if __name__ == '__main__':
    converter = AlphaConverter()
    app = App(converter)
    app.start()
# output    
# Converting currency using Alpha API
# 100 EUR = 120.0 USD

Source: pythontutorial.net

Similar codes

0 vote196 views4 answers
Randome Word generator from consonant, vowel and specific string
Python
0 vote189 views1 answer
What is type
Python
0 vote145 views1 answer
There is no difference in R between a string scalar and a vector of strings
Python
0 vote200 views1 answer
Limit characters in django template
Python
0 vote232 views1 answer
Recieve output from java python
Python
5 votes154 views4 answers
Fahrenheit to celsius python program
Python
1 vote181 views1 answer
Python your mom
Python
0 vote295 views1 answer
Python ValueError: zero-size array to reduction operation maximum which has no identity
Python
66 votes234 views4 answers
Iterate over rows dataframe
Python
2 votes187 views2 answers
Str replace pandas
Python