title: "Failed to import pydot" throws in kerasR
body: <p>I use the package keras under R and I would like to know if there was a command like python with plot_model () which allows to display its neuron network</p>
  
  <pre><code>library(keras)
  </code></pre>
  
  <p>for example I would like to display this neural network under R</p>
  
  <pre><code>  model &lt;- keras_model_sequential()
    model %&gt;%
      layer_dense(units = 5, input_shape = 2) %&gt;%
      layer_activation("relu") %&gt;%
      layer_dense(units = 1)
  </code></pre>
  
  <p>I install package kerasR for use the function plot_model(), but i have this error.</p>
  
  <pre><code>&gt; library(kerasR)
  &gt; plot_model(model)
  
  Error in py_call_impl(callable, dots$args, dots$keywords) : 
    ImportError: Failed to import pydot. You must install pydot and graphviz for `pydotprint` to work.
  
  Detailed traceback: 
    File "C:\Users\Idriss\ANACON~1\envs\R-TENS~1\lib\site-packages\keras\utils\vis_utils.py", line 131, in plot_model
      dot = model_to_dot(model, show_shapes, show_layer_names, rankdir)
    File "C:\Users\Idriss\ANACON~1\envs\R-TENS~1\lib\site-packages\keras\utils\vis_utils.py", line 52, in model_to_dot
      _check_pydot()
    File "C:\Users\Idriss\ANACON~1\envs\R-TENS~1\lib\site-packages\keras\utils\vis_utils.py", line 27, in _check_pydot
      raise ImportError('Failed to import pydot. You must install pydot'
  </code></pre>
  
  <p>I'm use windows 10 64 bits, i use RStudio with Anaconda</p>
  
  <hr>
  
  <p>In [4] pydot.Dot.create(pydot.Dot())</p>
  
  <pre><code>Out[4]: b"%!PS-Adobe-3.0\r\n%%Creator: graphviz version 2.38.0 (20140413.2041)\r\n%%Title: G\r\n%%Pages: (atend)\r\n%%BoundingBox: (atend)\r\n%%EndComments\r\nsave\r\n%%BeginProlog\r\n/DotDict 200 dict def\r\nDotDict begin\r\n\r\n/setupLatin1 {\r\nmark\r\n/EncodingVector 256 array def\r\n EncodingVector 0\r\n\r\nISOLatin1Encoding 0 255 getinterval putinterval\r\nEncodingVector 45 /hyphen put\r\n\r\n% Set up ISO Latin 1 character encoding\r\n/starnetISO {\r\n        dup dup findfont dup length dict begin\r\n        { 1 index /FID ne { def }{ pop pop } ifelse\r\n        } forall\r\n        /Encoding EncodingVector def\r\n        currentdict end definefont\r\n} def\r\n/Times-Roman starnetISO def\r\n/Times-Italic starnetISO def\r\n/Times-Bold starnetISO def\r\n/Times-BoldItalic starnetISO def\r\n/Helvetica starnetISO def\r\n/Helvetica-Oblique starnetISO def\r\n/Helvetica-Bold starnetISO def\r\n/Helvetica-BoldOblique starnetISO def\r\n/Courier starnetISO def\r\n/Courier-Oblique starnetISO def\r\n/Courier-Bold starnetISO def\r\n/Courier-BoldOblique starnetISO def\r\ncleartomark\r\n} bind def\r\n\r\n%%BeginResource: procset graphviz 0 0\r\n/coord-font-family /Times-Roman def\r\n/default-font-family /Times-Roman def\r\n/coordfont coord-font-family findfont 8 scalefont def\r\n\r\n/InvScaleFactor 1.0 def\r\n/set_scale {\r\n       dup 1 exch div /InvScaleFactor exch def\r\n       scale\r\n} bind def\r\n\r\n% styles\r\n/solid { [] 0 setdash } bind def\r\n/dashed { [9 InvScaleFactor mul dup ] 0 setdash } bind def\r\n/dotted { [1 InvScaleFactor mul 6 InvScaleFactor mul] 0 setdash } bind def\r\n/invis {/fill {newpath} def /stroke {newpath} def /show {pop newpath} def} bind def\r\n/bold { 2 setlinewidth } bind def\r\n/filled { } bind def\r\n/unfilled { } bind def\r\n/rounded { } bind def\r\n/diagonals { } bind def\r\n/tapered { } bind def\r\n\r\n% hooks for setting color \r\n/nodecolor { sethsbcolor } bind def\r\n/edgecolor { sethsbcolor } bind def\r\n/graphcolor { sethsbcolor } bind def\r\n/nopcolor {pop pop pop} bind def\r\n\r\n/beginpage {\t% i j npages\r\n\t/npages exch def\r\n\t/j exch def\r\n\t/i exch def\r\n\t/str 10 string def\r\n\tnpages 1 gt {\r\n\t\tgsave\r\n\t\t\tcoordfont setfont\r\n\t\t\t0 0 moveto\r\n\t\t\t(\\() show i str cvs show (,) show j str cvs show (\\)) show\r\n\t\tgrestore\r\n\t} if\r\n} bind def\r\n\r\n/set_font {\r\n\tfindfont exch\r\n\tscalefont setfont\r\n} def\r\n\r\n% draw text fitted to its expected width\r\n/alignedtext {\t\t\t% width text\r\n\t/text exch def\r\n\t/width exch def\r\n\tgsave\r\n\t\twidth 0 gt {\r\n\t\t\t[] 0 setdash\r\n\t\t\ttext stringwidth pop width exch sub text length div 0 text ashow\r\n\t\t} if\r\n\tgrestore\r\n} def\r\n\r\n/boxprim {\t\t\t\t% xcorner ycorner xsize ysize\r\n\t\t4 2 roll\r\n\t\tmoveto\r\n\t\t2 copy\r\n\t\texch 0 rlineto\r\n\t\t0 exch rlineto\r\n\t\tpop neg 0 rlineto\r\n\t\tclosepath\r\n} bind def\r\n\r\n/ellipse_path {\r\n\t/ry exch def\r\n\t/rx exch def\r\n\t/y exch def\r\n\t/x exch def\r\n\tmatrix currentmatrix\r\n\tnewpath\r\n\tx y translate\r\n\trx ry scale\r\n\t0 0 1 0 360 arc\r\n\tsetmatrix\r\n} bind def\r\n\r\n/endpage { showpage } bind def\r\n/showpage { } def\r\n\r\n/layercolorseq\r\n\t[\t% layer color sequence - darkest to lightest\r\n\t\t[0 0 0]\r\n\t\t[.2 .8 .8]\r\n\t\t[.4 .8 .8]\r\n\t\t[.6 .8 .8]\r\n\t\t[.8 .8 .8]\r\n\t]\r\ndef\r\n\r\n/layerlen layercolorseq length def\r\n\r\n/setlayer {/maxlayer exch def /curlayer exch def\r\n\tlayercolorseq curlayer 1 sub layerlen mod get\r\n\taload pop sethsbcolor\r\n\t/nodecolor {nopcolor} def\r\n\t/edgecolor {nopcolor} def\r\n\t/graphcolor {nopcolor} def\r\n} bind def\r\n\r\n/onlayer { curlayer ne {invis} if } def\r\n\r\n/onlayers {\r\n\t/myupper exch def\r\n\t/mylower exch def\r\n\tcurlayer mylower lt\r\n\tcurlayer myupper gt\r\n\tor\r\n\t{invis} if\r\n} def\r\n\r\n/curlayer 0 def\r\n\r\n%%EndResource\r\n%%EndProlog\r\n%%BeginSetup\r\n14 default-font-family set_font\r\n1 setmiterlimit\r\n% /arrowlength 10 def\r\n% /arrowwidth 5 def\r\n\r\n% make sure pdfmark is harmless for PS-interpreters other than Distiller\r\n/pdfmark where {pop} {userdict /pdfmark /cleartomark load put} ifelse\r\n% make '&lt;&lt;' and '&gt;&gt;' safe on PS Level 1 devices\r\n/languagelevel where {pop languagelevel}{1} ifelse\r\n2 lt {\r\n    userdict (&lt;&lt;) cvn ([) cvn load put\r\n    userdict (&gt;&gt;) cvn ([) cvn load put\r\n} if\r\n\r\n%%EndSetup\r\nsetupLatin1\r\n%%Page: 1 1\r\n%%PageBoundingBox: 36 36 44 44\r\n%%PageOrientation: Portrait\r\n0 0 1 beginpage\r\ngsave\r\n36 36 8 8 boxprim clip newpath\r\n1 1 set_scale 0 rotate 40 40 translate\r\nendpage\r\nshowpage\r\ngrestore\r\n%%PageTrailer\r\n%%EndPage: 1\r\n%%Trailer\r\n%%Pages: 1\r\n%%BoundingBox: 36 36 44 44\r\nend\r\nrestore\r\n%%EOF\r\n"
  </code></pre>