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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 schema_spec_from_tuple(tup):
 """Return the schema spec from a run-time tuple."""

  if hasattr(tup, 'get_schema_spec'):
    # Tuples have a TupleSchema field that contains a model of the schema
    return schema.from_spec({
        'fields': TupleSchemaAccess(tup),
        'required': tup.get_required_fields()})
  return schema.AnySchema()