Python 3.11 removed "U" mode breaks methods like text and lines

[charlesnagy]

_textmode is set to be by default "U" in pager/deps/path3.py. "U" mode was removed in Python 3.11 so that breaks methods such as text and others where encoding is not provided.

# Universal newline support
_textmode = 'U'
if hasattr(__builtins__, 'file') and not hasattr(file, 'newlines'):
    _textmode = 'r'

# ...

    def text(self, encoding=None, errors='strict'):
        """ ... """
        if encoding is None:
            # 8-bit
            f = self.open(_textmode)

Exception:

File "/Users/karolynagy/.virtualenvs/test/lib/python3.11/site-packages/paver/deps/path3.py", line 582, in text
    f = self.open(_textmode)
        ^^^^^^^^^^^^^^^^^^^^
  File "/Users/karolynagy/.virtualenvs/test/lib/python3.11/site-packages/paver/deps/path3.py", line 539, in open
    return open(self, mode)
           ^^^^^^^^^^^^^^^^
ValueError: invalid mode: 'U'

One fix to provide encoding when calling text method works. For example:

- options.assets.js_files = map(lambda x: (str(x), x.text()), files)
+ options.assets.js_files = map(lambda x: (str(x), x.text("utf8")), files)

However it would be good if the method didn't fail without parameters.

[Almad]

Thank you. I believe it's probably time to #190 given the issues like this