Save to .pdf doesn't work in 2.1.0 #9390

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TypeError                                 Traceback (most recent call last)
<ipython-input-3-5c7237786c15> in <module>()
      1 fig, ax = plt.subplots()
      2 ax.plot([5, 4, 2, 3])
----> 3 fig.savefig('test.pdf')

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\figure.py in savefig(self, fname, **kwargs)
   1812             self.set_frameon(frameon)
   1813 
-> 1814         self.canvas.print_figure(fname, **kwargs)
   1815 
   1816         if frameon:

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\backend_bases.py in print_figure(self, filename, dpi, facecolor, edgecolor, orientation, format, **kwargs)
   2257                 orientation=orientation,
   2258                 bbox_inches_restore=_bbox_inches_restore,
-> 2259                 **kwargs)
   2260         finally:
   2261             if bbox_inches and restore_bbox:

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\backends\backend_pdf.py in print_pdf(self, filename, **kwargs)
   2590                 RendererPdf(file, image_dpi, height, width),
   2591                 bbox_inches_restore=_bbox_inches_restore)
-> 2592             self.figure.draw(renderer)
   2593             renderer.finalize()
   2594             file.finalize()

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     53                 renderer.start_filter()
     54 
---> 55             return draw(artist, renderer, *args, **kwargs)
     56         finally:
     57             if artist.get_agg_filter() is not None:

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\figure.py in draw(self, renderer)
   1293 
   1294             mimage._draw_list_compositing_images(
-> 1295                 renderer, self, artists, self.suppressComposite)
   1296 
   1297             renderer.close_group('figure')

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\image.py in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    136     if not_composite or not has_images:
    137         for a in artists:
--> 138             a.draw(renderer)
    139     else:
    140         # Composite any adjacent images together

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     53                 renderer.start_filter()
     54 
---> 55             return draw(artist, renderer, *args, **kwargs)
     56         finally:
     57             if artist.get_agg_filter() is not None:

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\axes\_base.py in draw(self, renderer, inframe)
   2397             renderer.stop_rasterizing()
   2398 
-> 2399         mimage._draw_list_compositing_images(renderer, self, artists)
   2400 
   2401         renderer.close_group('axes')

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\image.py in _draw_list_compositing_images(renderer, parent, artists, suppress_composite)
    136     if not_composite or not has_images:
    137         for a in artists:
--> 138             a.draw(renderer)
    139     else:
    140         # Composite any adjacent images together

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     53                 renderer.start_filter()
     54 
---> 55             return draw(artist, renderer, *args, **kwargs)
     56         finally:
     57             if artist.get_agg_filter() is not None:

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\axis.py in draw(self, renderer, *args, **kwargs)
   1136 
   1137         for tick in ticks_to_draw:
-> 1138             tick.draw(renderer)
   1139 
   1140         # scale up the axis label box to also find the neighbors, not

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     53                 renderer.start_filter()
     54 
---> 55             return draw(artist, renderer, *args, **kwargs)
     56         finally:
     57             if artist.get_agg_filter() is not None:

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\axis.py in draw(self, renderer)
    280 
    281         if self.label1On:
--> 282             self.label1.draw(renderer)
    283         if self.label2On:
    284             self.label2.draw(renderer)

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\artist.py in draw_wrapper(artist, renderer, *args, **kwargs)
     53                 renderer.start_filter()
     54 
---> 55             return draw(artist, renderer, *args, **kwargs)
     56         finally:
     57             if artist.get_agg_filter() is not None:

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\text.py in draw(self, renderer)
    797                     textrenderer.draw_tex(gc, x, y, clean_line,
    798                                           textobj._fontproperties, angle,
--> 799                                           mtext=mtext)
    800                 else:
    801                     textrenderer.draw_text(gc, x, y, clean_line,

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\backends\backend_pdf.py in draw_tex(self, gc, x, y, s, prop, angle, ismath, mtext)
   1942         for x1, y1, dvifont, glyph, width in page.text:
   1943             if dvifont != oldfont:
-> 1944                 pdfname = self.file.dviFontName(dvifont)
   1945                 seq += [['font', pdfname, dvifont.size]]
   1946                 oldfont = dvifont

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\backends\backend_pdf.py in dviFontName(self, dvifont)
    686             return dvi_info.pdfname
    687 
--> 688         psfont = self.texFontMap[dvifont.texname]
    689         if psfont.filename is None:
    690             raise ValueError(

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\dviread.py in __getitem__(self, texname)
    864         fn, enc = result.filename, result.encoding
    865         if fn is not None and not fn.startswith(b'/'):
--> 866             fn = find_tex_file(fn)
    867         if enc is not None and not enc.startswith(b'/'):
    868             enc = find_tex_file(result.encoding)

D:\Programs\Miniconda\envs\py36\lib\site-packages\matplotlib\dviread.py in find_tex_file(filename, format)
   1043     # https://github.com/matplotlib/matplotlib/issues/633
   1044     pipe = subprocess.Popen(cmd, stdout=subprocess.PIPE,
-> 1045                             stderr=subprocess.PIPE)
   1046     result = pipe.communicate()[0].rstrip()
   1047     matplotlib.verbose.report('find_tex_file result: %s' % result,

D:\Programs\Miniconda\envs\py36\lib\subprocess.py in __init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags, restore_signals, start_new_session, pass_fds, encoding, errors)
    707                                 c2pread, c2pwrite,
    708                                 errread, errwrite,
--> 709                                 restore_signals, start_new_session)
    710         except:
    711             # Cleanup if the child failed starting.

D:\Programs\Miniconda\envs\py36\lib\subprocess.py in _execute_child(self, args, executable, preexec_fn, close_fds, pass_fds, cwd, env, startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite, unused_restore_signals, unused_start_new_session)
    969 
    970             if not isinstance(args, str):
--> 971                 args = list2cmdline(args)
    972 
    973             # Process startup details

D:\Programs\Miniconda\envs\py36\lib\subprocess.py in list2cmdline(seq)
    459             result.append(' ')
    460 
--> 461         needquote = (" " in arg) or ("\t" in arg) or not arg
    462         if needquote:
    463             result.append('"')

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