diff --git a/repo2docker/contentproviders/ckan.py b/repo2docker/contentproviders/ckan.py
index 2618fd06..7f0dec77 100644
--- a/repo2docker/contentproviders/ckan.py
+++ b/repo2docker/contentproviders/ckan.py
@@ -25,7 +25,7 @@ def _fetch_version(self, api_url):
         Borrowed from the Hydroshare provider.
         """
         package_show_url = f"{api_url}package_show?id={self.dataset_id}"
-        resp = self.urlopen(package_show_url).json()
+        resp = self.session.get(package_show_url).json()
         date = resp["result"]["metadata_modified"]
         parsed_date = datetime.strptime(date, "%Y-%m-%dT%H:%M:%S.%f")
         epoch = parsed_date.replace(tzinfo=timezone(timedelta(0))).timestamp()
@@ -35,8 +35,6 @@ def _fetch_version(self, api_url):
     def _request(self, url, **kwargs):
         return self.session.get(url, **kwargs)
 
-    urlopen = _request
-
     def detect(self, source, ref=None, extra_args=None):
         """Trigger this provider for things that resolve to a CKAN dataset."""
         parsed_url = urlparse(source)
@@ -58,7 +56,7 @@ def detect(self, source, ref=None, extra_args=None):
         ).geturl()
 
         status_show_url = f"{api_url}status_show"
-        resp = self.urlopen(status_show_url)
+        resp = self.session.get(status_show_url)
         if resp.status_code == 200:
 
             # Activity ID may be present either as a query parameter, activity_id
@@ -97,7 +95,7 @@ def fetch(self, spec, output_dir, yield_output=False):
                 {"id": dataset_id}
             )
 
-        resp = self.urlopen(
+        resp = self.session.get(
             fetch_url,
             headers={"accept": "application/json"},
         )
diff --git a/repo2docker/contentproviders/doi.py b/repo2docker/contentproviders/doi.py
index cf43a157..2dc34b56 100644
--- a/repo2docker/contentproviders/doi.py
+++ b/repo2docker/contentproviders/doi.py
@@ -27,21 +27,6 @@ def __init__(self):
     def _request(self, url, **kwargs):
         return self.session.get(url, **kwargs)
 
-    urlopen = _request
-
-    def _urlopen(self, req, headers=None):
-        """A urlopen() helper"""
-        # someone passed a string, not a request
-        if not isinstance(req, request.Request):
-            req = request.Request(req)
-
-        req.add_header("User-Agent", f"repo2docker {__version__}")
-        if headers is not None:
-            for key, value in headers.items():
-                req.add_header(key, value)
-
-        return request.urlopen(req)
-
     def doi2url(self, doi):
         # Transform a DOI to a URL
         # If not a doi, assume we have a URL and return
diff --git a/repo2docker/contentproviders/figshare.py b/repo2docker/contentproviders/figshare.py
index 6c7b26c8..e8fec3fe 100644
--- a/repo2docker/contentproviders/figshare.py
+++ b/repo2docker/contentproviders/figshare.py
@@ -74,7 +74,7 @@ def fetch(self, spec, output_dir, yield_output=False):
         host = spec["host"]
 
         yield f"Fetching Figshare article {article_id} in version {article_version}.\n"
-        resp = self.urlopen(
+        resp = self.session.get(
             f'{host["api"]}{article_id}/versions/{article_version}',
             headers={"accept": "application/json"},
         )
diff --git a/repo2docker/contentproviders/hydroshare.py b/repo2docker/contentproviders/hydroshare.py
index 4104d97a..90c41914 100755
--- a/repo2docker/contentproviders/hydroshare.py
+++ b/repo2docker/contentproviders/hydroshare.py
@@ -15,7 +15,7 @@ class Hydroshare(DoiProvider):
 
     def _fetch_version(self, host):
         """Fetch resource modified date and convert to epoch"""
-        json_response = self.urlopen(host["version"].format(self.resource_id)).json()
+        json_response = self.session.get(host["version"].format(self.resource_id)).json()
         date = next(
             item for item in json_response["dates"] if item["type"] == "modified"
         )["start_date"]
@@ -63,7 +63,7 @@ def fetch(self, spec, output_dir, yield_output=False, timeout=120):
         yield f"Downloading {bag_url}.\n"
 
         # bag downloads are prepared on demand and may need some time
-        conn = self.urlopen(bag_url)
+        conn = self.session.get(bag_url)
         total_wait_time = 0
         while (
             conn.status_code == 200
@@ -77,7 +77,7 @@ def fetch(self, spec, output_dir, yield_output=False, timeout=120):
                 raise ContentProviderException(msg)
             yield f"Bag is being prepared, requesting again in {wait_time} seconds.\n"
             time.sleep(wait_time)
-            conn = self.urlopen(bag_url)
+            conn = self.session.get(bag_url)
         if conn.status_code != 200:
             msg = f"Failed to download bag. status code {conn.status_code}.\n"
             yield msg
diff --git a/repo2docker/contentproviders/zenodo.py b/repo2docker/contentproviders/zenodo.py
index 6982c3a7..31ea1741 100644
--- a/repo2docker/contentproviders/zenodo.py
+++ b/repo2docker/contentproviders/zenodo.py
@@ -73,7 +73,7 @@ def fetch(self, spec, output_dir, yield_output=False):
         host = spec["host"]
 
         yield f"Fetching Zenodo record {record_id}.\n"
-        resp = self.urlopen(
+        resp = self.session.get(
             f'{host["api"]}{record_id}',
             headers={"accept": "application/json"},
         )
@@ -82,7 +82,7 @@ def fetch(self, spec, output_dir, yield_output=False):
         if host["files"]:
             yield f"Fetching Zenodo record {record_id} files.\n"
             files_url = deep_get(record, host["files"])
-            resp = self.urlopen(
+            resp = self.session.get(
                 files_url,
                 headers={"accept": "application/json"},
             )
diff --git a/setup.py b/setup.py
index 58abff7c..d37aa17c 100644
--- a/setup.py
+++ b/setup.py
@@ -26,11 +26,10 @@ def finalize_options(self):
 
     def run(self):
         import json
-        from urllib.request import urlopen
+        import requests
 
-        resp = urlopen(self.url, timeout=5)
-        resp_body = resp.read()
-        data = json.loads(resp_body.decode("utf-8"))
+        resp = requests.get(self.url)
+        data = resp.json()
         if "installations" not in data:
             raise ValueError("Malformed installation map.")
 
diff --git a/tests/unit/contentproviders/test_doi.py b/tests/unit/contentproviders/test_doi.py
index 58cae5f5..f2de2b50 100644
--- a/tests/unit/contentproviders/test_doi.py
+++ b/tests/unit/contentproviders/test_doi.py
@@ -24,7 +24,7 @@ def test_url_headers(requests_mock):
     doi = DoiProvider()
 
     headers = {"test1": "value1", "Test2": "value2"}
-    result = doi.urlopen("https://mybinder.org", headers=headers)
+    result = doi.session.get("https://mybinder.org", headers=headers)
     assert "test1" in result.request.headers
     assert "Test2" in result.request.headers
     assert result.request.headers["User-Agent"] == f"repo2docker {__version__}"
diff --git a/tests/unit/contentproviders/test_figshare.py b/tests/unit/contentproviders/test_figshare.py
index 760c0e48..881c8513 100644
--- a/tests/unit/contentproviders/test_figshare.py
+++ b/tests/unit/contentproviders/test_figshare.py
@@ -5,7 +5,6 @@
 from io import BytesIO
 from tempfile import NamedTemporaryFile, TemporaryDirectory
 from unittest.mock import patch
-from urllib.request import Request, urlopen
 from zipfile import ZipFile
 
 import pytest
diff --git a/tests/unit/contentproviders/test_zenodo.py b/tests/unit/contentproviders/test_zenodo.py
index a1e1226f..1152ce2c 100644
--- a/tests/unit/contentproviders/test_zenodo.py
+++ b/tests/unit/contentproviders/test_zenodo.py
@@ -5,7 +5,6 @@
 from io import BytesIO
 from tempfile import NamedTemporaryFile, TemporaryDirectory
 from unittest.mock import patch
-from urllib.request import Request, urlopen
 from zipfile import ZipFile
 
 import pytest