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Output of helm version: v2.9.2
Output of kubectl version: 1.7.6

Cloud Provider/Platform (AKS, GKE, Minikube etc.):

When using 'helm package my-chart' to pack my chart. The archive seems to be okey. But when I try to unzip that archive, the files in the folder all have the wrong time stamp which is: 1969-12-31 19:00:00.