Out of order bug

environment.yml

name: plotly_express
dependencies:
  - python=3.5
  - numpy
  - matplotlib
  - pandas
  - scikit-learn
  - pip:
    - plotly==3.7.1
    - plotly_express

example.ipynb

{
  "cells": [
    {
      "cell_type": "code",
      "source": [
        "import plotly_express as px\n",
        "import plotly\n",
        "import pandas as pd\n",
        "print(plotly.__version__, pd.__version__)"
      ],
      "outputs": [],
      "execution_count": null,
      "metadata": {
        "_uuid": "107552f24aeabd6ed8cd0e09a2bed134d7e4e3e0"
      }
    },
    {
      "cell_type": "code",
      "source": [
        "%matplotlib inline\n",
        "from sklearn.datasets import make_blobs, make_moons, make_swiss_roll\n",
        "import matplotlib.pyplot as plt\n",
        "import numpy as np\n",
        "import pandas as pd\n",
        "from string import ascii_lowercase\n",
        "out_pt_list = []\n",
        "for frame, std in enumerate(np.linspace(0.1, 2, 50)):\n",
        "    blob_data = make_blobs(n_samples=100, \n",
        "                           cluster_std=std,\n",
        "                           centers=4,\n",
        "                           random_state=2019)\n",
        "    test_pts = pd.DataFrame(blob_data[0], columns=['x', 'y'])\n",
        "    test_pts['group'] = [ascii_lowercase[x] for x in blob_data[1]]\n",
        "    test_pts['frame'] = frame\n",
        "    out_pt_list += [test_pts]\n",
        "out_pt_df = pd.concat(out_pt_list, sort=False).reset_index(drop=True)\n",
        "out_pt_df.sample(5)"
      ],
      "outputs": [],
      "execution_count": null,
      "metadata": {
        "_cell_guid": "b1076dfc-b9ad-4769-8c92-a6c4dae69d19",
        "_uuid": "8f2839f25d086af736a60e9eeb907d3b93b6e0e5"
      }
    },
    {
      "cell_type": "code",
      "source": [
        "px.scatter(out_pt_df, \n",
        "           x='x', y='y',  \n",
        "           animation_frame='frame', \n",
        "           color='group')"
      ],
      "outputs": [],
      "execution_count": null,
      "metadata": {
        "_uuid": "64b339e21985a7079be7befe990721a567fd6836"
      }
    },
    {
      "cell_type": "code",
      "source": [],
      "outputs": [],
      "execution_count": null,
      "metadata": {
        "_uuid": "de21ac44e703e4f5f2d97e9e4796e85c40120021"
      }
    }
  ],
  "metadata": {
    "kernelspec": {
      "name": "python3",
      "language": "python",
      "display_name": "Python 3"
    },
    "language_info": {
      "name": "python",
      "version": "3.6.5",
      "mimetype": "text/x-python",
      "codemirror_mode": {
        "name": "ipython",
        "version": 3
      },
      "pygments_lexer": "ipython3",
      "nbconvert_exporter": "python",
      "file_extension": ".py"
    },
    "kernel_info": {
      "name": "python3"
    },
    "nteract": {
      "version": "0.12.3"
    }
  },
  "nbformat": 4,
  "nbformat_minor": 1
}

to run the notebook use mybinder at https://mybinder.org/v2/gist/kmader/7a182744194a5330008b6e40d60aea6b/master?filepath=example.ipynb