connection error

[chengyi-chris]

When I run first code

# Create a DataFrame object
from pandasticsearch import DataFrame
df = DataFrame.from_es(url='http://localhost:9200', index='people', username='username', password='username')

# Print the schema(mapping) of the index
df.print_schema()

then print error

/Library/Frameworks/Python.framework/Versions/3.8/lib/python3.8/base64.py in b64encode(s, altchars)
     56     application to e.g. generate url or filesystem safe Base64 strings.
     57     """
---> 58     encoded = binascii.b2a_base64(s, newline=False)
     59     if altchars is not None:
     60         assert len(altchars) == 2, repr(altchars)

TypeError: a bytes-like object is required, not 'str'

Am I enter an error? or how to fix that bugs?