message: More on python code conv
diff: import duckdb
  import pandas as pd
  import numpy
  +import sys
  def round_trip(data,pandas_type):
  df_in = pd.DataFrame({
  @@ -8,6 +9,8 @@ def round_trip(data,pandas_type):
  })
  df_out = duckdb.query_df(df_in, "data", "SELECT * FROM data").df()
  + print (df_out)
  + print (df_in)
  assert numpy.all(df_out['object'] == data)
  class TestPandasTypes(object):
  @@ -32,4 +35,24 @@ class TestPandasTypes(object):
  assert df_out['object'][0] == df_in['object'][0]
  assert df_out['object'][1] == df_in['object'][1]
  assert df_out['object'][2] == df_in['object'][2]
  - assert np.isnan(df_out['object'][3])
  \ No newline at end of file
  + assert numpy.isnan(df_out['object'][3])
  +
  + def test_pandas_interval(self, duckdb_cursor):
  + data = numpy.array([2069211000000000,numpy.datetime64("NaT")])
  + df_in = pd.DataFrame({
  + 'object': pd.Series(data, dtype='timedelta64[ns]'),
  + })
  +
  + df_out = duckdb.query_df(df_in, "data", "SELECT * FROM data").df()
  +
  + assert df_out['object'][0] == df_in['object'][0]
  + assert pd.isnull(df_out['object'][1])
  +
  + def test_pandas_encoded_utf8(self, duckdb_cursor):
  + if sys.version_info.major < 3:
  + return
  + data = u'\u00c3' # Unicode data
  + data = [data.encode('utf8')]
  + round_trip(data,'string')
  +
  +
  