19 using System.Collections;
20 using System.Collections.Generic;
30 private IEnumerable<Slice> _data;
32 private PyObject _dataframe;
60 var expiry = _data.SelectMany(x => x.FuturesChains.SelectMany(y => y.Value.Contracts.Keys.Select(z => z.ID.Date).Distinct()));
63 return expiry.Distinct().ToList().ToPython();
76 #region IEnumerable implementation
78 public IEnumerator<Slice> GetEnumerator()
80 return _data.GetEnumerator();
83 IEnumerator IEnumerable.GetEnumerator()
85 return GetEnumerator();