TypeError を解決する方法: \'str\' はテキストを圧縮するときに Python 3 のバッファー インターフェイスをサポートしていませんか?

plaintext = input("Please enter the text you want to compress")
filename = input("Please enter the desired filename")
with gzip.open(filename + ".gz", "wb") as outfile:
    outfile.write(bytes(plaintext, 'UTF-8'))

plaintext = 'Polish text: ąćęłńóśźżĄĆĘŁŃÓŚŹŻ'
filename = 'foo.gz'
with gzip.open(filename, 'wb') as outfile:
    outfile.write(bytes(plaintext, 'UTF-8'))
with gzip.open(filename, 'r') as infile:
    outfile_content = infile.read().decode('UTF-8')
print(outfile_content)