Use pathlib in packaging.py, io.py, and gen_latex_symbols.py

* Added pathlib in a few places where it makes sense to.

IPython/core/magics/packaging.py

@@ -11,6 +11,7 b''
 import re
 import shlex
 import sys
+from Pathlib import Path
 
 from pathlib import Path
 from IPython.core.magic import Magics, magics_class, line_magic

IPython/utils/io.py

@@ -14,6 +14,7 b' import sys'
 import tempfile
 import warnings
 from warnings import warn
+from pathlib import Path
 
 from IPython.utils.decorators import undoc
 from .capture import CapturedIO, capture_output
@@ -204,8 +205,8 b" def temp_pyfile(src, ext='.py'):"
     (filename, open filehandle)
       It is the caller's responsibility to close the open file and unlink it.
     """
-    fname = tempfile.mkstemp(ext)[1]
-    with open(fname,'w') as f:
+    fname = Path(tempfile.mkstemp(ext)[1])
+    with fname.open('w') as f:
         f.write(src)
         f.flush()
     return fname

tools/gen_latex_symbols.py

@@ -9,7 +9,7 b''
 # 
 # The original mapping of latex symbols to unicode comes from the `latex_symbols.jl` files from Julia.
 
-import os, sys
+from pathlib import Path
 
 # Import the Julia LaTeX symbols
 print('Importing latex_symbols.js from Julia...')
@@ -80,9 +80,8 b' s += """'
 reverse_latex_symbol = { v:k for k,v in latex_symbols.items()}
 """
 
-fn = os.path.join('..','IPython','core','latex_symbols.py')
-print("Writing the file: %s" % fn)
-with open(fn, 'w', encoding='utf-8') as f:
-    f.write(s)
+fn = Path('..', 'IPython', 'core', 'latex_symbols.py')
+print("Writing the file: %s" % str(fn))
+fn.write_text(s, encoding='utf-8')