This is equivalent to calling str(object) or repr(object) in Python.
py_repr(object)py_str(object, ...)
Character vector
Python object
Unused
In Python, calling print() invokes the builtin str(), while auto-printing
an object at the REPL invokes the builtin repr().
In R, the default print method for python objects invokes py_repr(), and
the default format() and as.character() methods invoke py_str().
For historical reasons, py_str() is also an R S3 method that allows R
authors to customize the the string representation of a Python object from R.
New code is recommended to provide a format() and/or print() S3 R method
for python objects instead.
The default implementation will call PyObject_Str on the object.