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In-depth tutorials: 20
Topics covered: 7
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learn.py

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def learn(topic, days=30):
    """Small steps, every single day."""
    skills = []
    for day in range(1, days + 1):
        skills.append(practice(topic, day))
        if day % 7 == 0:
            build_project(topic, skills)
    return f"Confident in {topic}!"

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Numbers 1 to 4 flow through n * n and become the list 1, 4, 9, 16

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