A drop-in replacement for some limited uses of curl, written using only Python3 standard libraries.

hcat

#!/usr/bin/env python3
# Makes an HTTP request to the specified URL and sends response to stdout.
# A drop-in replacement for some limited uses of curl, like:
#   hcat $URL -H "Authorization: Bearer $TOKEN"

import urllib.parse
import urllib.request
import sys
import argparse

def dictify(kvs, sep):
    d = {}
    for h in kvs or []:
        k, _, v = h.partition(sep)
        d[k] = v
    return d

parser = argparse.ArgumentParser(description = 'A drop-in replacement for certain uses of curl')
parser.add_argument('path')
parser.add_argument('-X', '--request')
parser.add_argument('-H', '--header', action='append')
parser.add_argument('--data-urlencode', action='append')
args = parser.parse_args()
method = args.request or ('POST' if args.data_urlencode else 'GET')
headers = dictify(args.header, ': ')
parameters = dictify(args.data_urlencode, '=')
data = urllib.parse.urlencode(parameters).encode('ascii') or None
req = urllib.request.Request(args.path, method=method, headers=headers, data=data)
with urllib.request.urlopen(req) as response:
    sys.stdout.buffer.write(response.read())