# data_buffer.py

data_stream = []

def add_data(industry, demand, customers):
    data_stream.append({
        "industry": industry,
        "demand": demand,
        "customers": customers
    })

    if len(data_stream) > 50:
        data_stream.pop(0)

def get_latest(industry, n=10):
    return [d for d in data_stream if d["industry"] == industry][-n:]