<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def schema_map(schema):
 """Return a valid ICachedItemMapper.map for schema"""

    mapper = {}
    for name in getFieldNames(schema):
        mapper[name] = name
    return mapper