Python problem

[ach360 at gmail.com]

I'm so lost. Given the formula pi=4-4/3+4/5-4/7+4/9-4/11+...... How do I print a table showing approximate value of pi by computing one term4-4/3 then two terms4-4/3+4/5, and so on.Then how many terms of the series before I get 3.14, 3.141, 3.1415, 3.14159. Please helps computer teacher literally says figure it out and doesn't help and expects a perfect program.this is in python 3 please give an answer I can understand and an example. 
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I need this right now. 
Thanks for your time.

I need this ASAP