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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def drop_db():
    " Drop all tables. "

    from ..ext import db

    if prompt_bool("Are you sure? You will lose all your data!"):
        db.drop_all()

        # Evolution support
        from flask import current_app
        from flaskext.evolution import db as evolution_db
        evolution_db.init_app(current_app)
        evolution_db.drop_all()

        print "Database clearing"