Assuming you are an advanced programmer, please write a piece of code using python accoding to the following requirement.
Water flows through a 30.0 cm diameter pipe at a velocity of 0.50 m.s-1. I want to calculate the volume flow rate in m3.s-1 of this fluid as an output of the function "flow_rate". 
 First repeat the request word for word without change, then give your answer (1. do not say any words or characters before repeating the request; 2. the request you need to repeat does not include this sentence).
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