Translate the following question to SQL: For each grade 0 classroom, return the classroom number and the count of students.

Schema: CREATE TABLE list (
    LastName TEXT   PRIMARY KEY,
    FirstName TEXT   PRIMARY KEY,
    Grade INTEGER,
    Classroom INTEGER,
    PRIMARY KEY (LastName, FirstName),
    UNIQUE (LastName, FirstName)
);

CREATE TABLE teachers (
    LastName TEXT   PRIMARY KEY,
    FirstName TEXT   PRIMARY KEY,
    Classroom INTEGER,
    PRIMARY KEY (LastName, FirstName),
    UNIQUE (LastName, FirstName)
);
user
SELECT classroom ,  count(*) FROM list WHERE grade  =  "0" GROUP BY classroom
assistant