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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():
 """Drops the local database."""

    local_machine()
    with fab_settings(warn_only=True):
        local('psql {0} -c "DROP DATABASE {1}"'.format(
            USER_AND_HOST, env.db_name))
        local('psql {0} -c "DROP USER {1}"'.format(
            USER_AND_HOST, env.db_role))