code: def get_tree_from_sha(self, ref):
          '''
          Return a pygit2.Tree object matching a SHA
          '''
          try:
              return self.repo.revparse_single(ref).tree
          except (KeyError, TypeError, ValueError, AttributeError):
              return Nonf get_tree_from_sha(self, ref):
          '''
          Return a pygit2.Tree object matching a SHA
          '''
          try:
              return self.repo.revparse_single(ref).tree
          except (KeyError, TypeError, ValueError, AttributeError):
              return None
docs: Return a pygit2.Tree object matching a SHA