message: change to using 'ascii_lowercase'
diff: import duckdb
  import pandas as pd
  import numpy
  +import string
  def round_trip(data,pandas_type):
  df_in = pd.DataFrame({
  @@ -46,19 +47,19 @@ class TestPandasTypes(object):
  # c=type2
  # ..
  data = {}
  - for i, dtype in enumerate(data_types):
  - data[chr(ord("a")+i)] = base_df.a.astype(dtype)
  + for letter, dtype in zip(string.ascii_lowercase, data_types):
  + data[letter] = base_df.a.astype(dtype)
  df = pd.DataFrame.from_dict(data)
  out_df = duckdb.default_connection.execute('select * from df').df()
  # Verify that the types in the out_df are correct
  # FIXME: we don't support outputting pandas specific types (i.e UInt64)
  - for i, item in enumerate(data_types):
  - column_name = chr(ord("a")+i)
  + for letter, item in zip(string.ascii_lowercase, data_types):
  + column_name = letter
  assert(str(df[column_name].dtype) == item)
  - for i, item in enumerate(data_types):
  - column_name = chr(ord("a")+i)
  + for letter, item in zip(string.ascii_lowercase, data_types):
  + column_name = letter
  assert(str(out_df[column_name].dtype) == item.lower())
  def test_pandas_unsigned(self, duckdb_cursor):
  