In determining the period for which the taxpayer has held property received in an exchange, there shall be included the period for which he held the property exchanged if, under this chapter, the property has, for the purpose of determining gain or loss from a sale or exchange, the same basis in whole or in part in his hands as the property exchanged, and, in the case of such exchanges the property exchanged at the time of such exchange was a capital asset as defined in section 1221 or property described in section 1231. For purposes of this paragraph—