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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 readddl(db):
    '''Walks down database objects and generates
    JDOC objects for table descriptions'''
    jdoc = []
    for schema in db.contents:
        j = JDOC(None,
                 schema.object_name,
                 schema.comment,
                 schema.object_type)
        jdoc.append(j)
        for table in schema.contents:
            j = JDOC(table.schema_name,
                     table.object_name,
                     table.comment,
                     table.object_type)
            for c in table.contents:
                j.params.append(c)
            jdoc.append(j)
    return jdoc