A simple installer script to install simplex by Blur. Simply run this in Python in maya

simplexInstaller.py

from maya import cmds as mc
import urllib2
import os
import zipfile
import shutil


def downloadRelease():
    userTmpDir = mc.internalVar(userTmpDir=True)
    dest = os.path.join(userTmpDir, 'simplex.zip')
    if os.path.exists(dest):
        mc.warning("Download already exists at %s. Not redownloading." % dest)
        return dest

    with open(dest, 'wb') as f:
        f.write(urllib2.urlopen('https://github.com/blurstudio/Simplex/releases/download/1.0.3/Simplex.zip').read())
    
    mc.warning("Download Complete! Downloaded to %s" % dest)
    return dest

def extract(filepath):
    mc.warning("Extracting file")
    scriptDir = mc.internalVar(userScriptDir=True)
    target = os.path.join(scriptDir, 'Simplex')
    if os.path.exists(target):
        mc.warning("Simplex is already extracted here: %s" % target)
        return target

    with zipfile.ZipFile(filepath, 'r') as z:
        z.extractall(scriptDir)

    if not os.path.exists(target):
        mc.error("Could not find the Simplex directory at %s" % target)

    mc.warning("Extracted Simplex to %s" % target)
    return target

def moveMod(location):
    modFile = os.path.join(location, 'simplex.mod')
    scriptDir = mc.internalVar(userScriptDir=True)
    modDir = os.path.join(os.path.dirname(os.path.dirname(scriptDir)), 'modules')
    target = os.path.join(modDir, 'simplex.mod')

    if os.path.exists(target):
        mc.warning("Mod file already exists here %s. Not Overwriting" % target)
        return target

    if not os.path.exists(modFile):
        mc.error("The modfile doesn't exist here: %s" % modFile)

    if not os.path.exists(modDir):
        mc.warning("Creating modules directory: %s" % modDir)
        os.mkdir(modDir)

    shutil.copy2(modFile, target)
    return target

def changeMod(mod, location):
    with open(mod, 'r') as f:
        contents = f.read()
    
    contents = contents.replace('<FILEPATH>', location)
    with open(mod, 'w') as f:
        f.write(contents)

    mc.warning("Wrote changes to modfile")

def loadPlugin(location):
    version = mc.about(version=True)
    plugin = os.path.join(location, 'maya%s/plug-ins' % version, 'simplex_maya.mll')

    if not os.path.exists(plugin):
        mc.error("Could not find plugin here %s" % plugin)

    mc.loadPlugin(plugin)

def moveUI(location):
    uiDir = os.path.join(location, 'SimplexUI')
    scriptDir = mc.internalVar(userScriptDir=True)

    target = os.path.join(scriptDir, 'SimplexUI')
    if not os.path.exists(target):
        mc.warning("Copying SimplexUI to scripts directory so it can be imported")
        shutil.copytree(uiDir, target)

    return target

def run():
    from SimplexUI import runSimplexUI
    runSimplexUI()

def main():
    download = downloadRelease()
    location = extract(download)
    mod = moveMod(location)
    changeMod(mod, location)
    loadPlugin(location)
    moveUI(location)
    run()

    mc.confirmDialog(title="Restart Maya", message=(
        "You may need to restart maya and then load the simplex_maya.mll plugin\n"
        "Then run this in python:\n\n"
        "from SimplexUI import runSimplexUI\n"
        "runSimplexUI()"
        )
    
    )
if __name__ == '__main__':
    main()