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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 _diffSchema(diskSchema, memorySchema):
 """ Format a schema mismatch for human consumption. @param diskSchema: The on-disk schema. @param memorySchema: The in-memory schema. @rtype: L{bytes} @return: A description of the schema differences. """

    diskSchema = set(diskSchema)
    memorySchema = set(memorySchema)
    diskOnly = diskSchema - memorySchema
    memoryOnly = memorySchema - diskSchema
    diff = []
    if diskOnly:
        diff.append('Only on disk:')
        diff.extend(map(repr, diskOnly))
    if memoryOnly:
        diff.append('Only in memory:')
        diff.extend(map(repr, memoryOnly))
    return '\n'.join(diff)