docs: def convert_numpy_type(cls, dtype):
          """Convert a numpy dtype into a Column datatype. Only handles common
          types.
  
          Implemented as a function to decouple from numpy
  
          """
  
          m = {
              'int64': cls.DATATYPE_INTEGER64,
              'float64': cls.DATATYPE_FLOAT,
              'object': cls.DATATYPE_TEXT  # Hack. Pandas makes strings into object.
          }
  
          t = m.get(dtype.name, None)
  
          if not t:
              raise TypeError(
                  "Failed to convert numpy type: '{}' ".format(
                      dtype.name))
  
          return t