(self, field_mask=None)
Initializes the tree by FieldMask.
Initializes the tree by FieldMask.
Initializes the tree by FieldMask .
def __init__(self, field_mask=None):
    """Initializes the tree by FieldMask."""
    self._root = {}
    if field_mask:
      self.MergeFromFieldMask(field_mask)
def __init__ ( self , field_mask = None ) : self . _root = { } if field_mask : self . MergeFromFieldMask ( field_mask )