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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 Lesson 21
Step1:  This gets harder with more variables.
Step2:  Python has string interpolation, which uses %s to insert other strings into placeholders.
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Python Code:
'hello ' + 'world!'
Explanation: Lesson 21:
String Formatting
You can typically combine strings with +.
End of explanation
name = 'Alice'
place = 'Main Street'
time = '6 pm'
food = 'turnips'
print('Hello ' + name + ', you are invited to a party at ' + place + ' at ' + time + '. Please bring ' + food + '.')
Explanation: This gets harder with more variables.
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print(' Hello %s, you are invited to a party at %s at %s. Please bring %s.' % (name, place, time, food)) 
Explanation: Python has string interpolation, which uses %s to insert other strings into placeholders.
End of explanation
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