Datapusher Install Issues

I'm trying to install Datapusher on a development instance of CKAN.

When I go to install requirements using `pip install -r requirements-dev.txt `, this happens:

` Stored in directory: /home/uhc-ckan/.cache/pip/wheels/f2/9a/90/de94f8556265ddc9d9c8b271b0f63e57b26fb1d67a45564511
Successfully built ckanserviceprovider messytables python-slugify httpretty nose SQLAlchemy flask-login json-table-schema pycparser
ERROR: ckanserviceprovider 0.0.9 has requirement requests>=2.20.0, but you'll have requests 2.13.0 which is incompatible.
Installing collected packages: APScheduler, Werkzeug, Jinja2, Flask, SQLAlchemy, idna, asn1crypto, enum34, ipaddress, pycparser, cffi, cryptography, pyOpenSSL, requests, flask-login, ckanserviceprovider, xlrd, cha
rdet, lxml, json-table-schema, messytables, Unidecode, python-slugify, certifi, httpretty, nose
Found existing installation: Werkzeug 0.14.1
Uninstalling Werkzeug-0.14.1:
Successfully uninstalled Werkzeug-0.14.1
Found existing installation: Jinja2 2.8
Uninstalling Jinja2-2.8:
Successfully uninstalled Jinja2-2.8
Found existing installation: Flask 0.12.4
Uninstalling Flask-0.12.4:
Successfully uninstalled Flask-0.12.4
Found existing installation: SQLAlchemy 1.1.11
Uninstalling SQLAlchemy-1.1.11:
Successfully uninstalled SQLAlchemy-1.1.11
Found existing installation: requests 2.11.1
Uninstalling requests-2.11.1:
Successfully uninstalled requests-2.11.1
Found existing installation: python-slugify 3.0.2
Uninstalling python-slugify-3.0.2:
Successfully uninstalled python-slugify-3.0.2
Found existing installation: nose 1.3.7
Uninstalling nose-1.3.7:
Successfully uninstalled nose-1.3.7
Successfully installed APScheduler-2.1.2 Flask-1.1.1 Jinja2-2.10.1 SQLAlchemy-1.3.6 Unidecode-1.1.1 Werkzeug-0.15.5 asn1crypto-0.24.0 certifi-2019.6.16 cffi-1.12.3 chardet-3.0.4 ckanserviceprovider-0.0.9 cryptogra
phy-2.7 enum34-1.1.6 flask-login-0.4.1 httpretty-0.9.4 idna-2.8 ipaddress-1.0.22 json-table-schema-0.2.1 lxml-4.4.0 messytables-0.15.2 nose-1.2.1 pyOpenSSL-19.0.0 pycparser-2.19 python-slugify-1.2.1 requests-2.13.
0 xlrd-1.2.0 `

This reinstalls a bunch of stuff, and causes problems with CKAN, and I get odd errors when attempting to start CKAN, like `ValueError: VDM only works with SQLAlchemy versions 0.4 through 0.9, not: 1.3.6 `

So I reverted back to a earlier checkpoint on my VM, and try to proceed without installing the requirements, and get this message when trying to start the datapusher:

`python: can't open file 'example/main.py': [Errno 2] No such file or directory
`
Does anyone know what could be going wrong there?