diff --git a/py_ecc/secp256k1/secp256k1.py b/py_ecc/secp256k1/secp256k1.py
index 68f1ca1..db93ee5 100644
--- a/py_ecc/secp256k1/secp256k1.py
+++ b/py_ecc/secp256k1/secp256k1.py
@@ -6,8 +6,11 @@ import sys
 if sys.version_info.major == 2:
     safe_ord = ord
 else:
-    def safe_ord(x):
-        return x
+    def safe_ord(value):
+        if isinstance(value, int):
+            return value
+        else:
+            return ord(value)
 
 
 # Elliptic curve parameters (secp256k1)

secp256k1.py fails on Python 3.4
Error test:

```python
import binascii
import rlp
# sha3 from module `pysha3` not `ssh3`
import sha3
from py_ecc.secp256k1 import ecdsa_raw_recover

n = 0
p = 20000000000
g = 100000
v = 1000
Tn = ''
Tp = p.to_bytes((p.bit_length()//8) + 1,byteorder='big')
Tg = g.to_bytes((g.bit_length()//8) + 1,byteorder='big')
Tt = binascii.unhexlify("687422eEA2cB73B5d3e242bA5456b782919AFc85")
Tv = v.to_bytes((v.bit_length()//8) + 1,byteorder='big')
Td = binascii.unhexlify("c0de")
transaction = [Tn, Tp, Tg, Tt, Tv, Td]
rlp_data=rlp.encode(transaction)
unsigned_message=sha3.keccak_256(rlp_data).hexdigest()
v = 28
r = int("5897c2c7c7412b0a555fb6f053ddb6047c59666bbebc6f5573134e074992d841",16)
s = int("1c71d1c62b74caff8695a186e2a24dd701070ba9946748318135e3ac0950b1d4",16)
ecdsa_raw_recover(unsigned_message, (v, r, s))
```

Error message:

> Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/apalau/python3.4/lib64/python3.4/site-packages/py_ecc/secp256k1/secp256k1.py", line 132, in ecdsa_raw_recover
    z = bytes_to_int(msghash)
  File "/home/apalau/python3.4/lib64/python3.4/site-packages/py_ecc/secp256k1/secp256k1.py", line 21, in bytes_to_int
    o = (o << 8) + safe_ord(b)
TypeError: unsupported operand type(s) for +: 'int' and 'str'

On Python 2.7 the same `ecdsa_raw_recover(unsigned_message, (v, r, s))` works well.

Python version:

> python --version
> Python 3.4.5

diff --git a/tests/test_secp256k1.py b/tests/test_secp256k1.py
index c7fbe23..a56bba1 100644
--- a/tests/test_secp256k1.py
+++ b/tests/test_secp256k1.py
@@ -12,3 +12,11 @@ def test_privtopub():
 def test_ecdsa_raw_sign():
     v, r, s = ecdsa_raw_sign(b'\x35' * 32, priv)
     assert ecdsa_raw_recover(b'\x35' * 32, (v, r, s)) == pub
+
+
+def test_issue_4_bug():
+    unsigned_message = '6a74f15f29c3227c5d1d2e27894da58d417a484ef53bc7aa57ee323b42ded656'
+    v = 28
+    r = int("5897c2c7c7412b0a555fb6f053ddb6047c59666bbebc6f5573134e074992d841", 16)
+    s = int("1c71d1c62b74caff8695a186e2a24dd701070ba9946748318135e3ac0950b1d4", 16)
+    ecdsa_raw_recover(unsigned_message, (v, r, s))

pip install -e .
parse_log_pytest
pytest
pytest pytest-xdist
apt-get update apt-get install -y gcc
3.6
pytest --no-header -rA --tb=line --color=no -p no:cacheprovider -W ignore::DeprecationWarning
attrs @ file:///opt/conda/conda-bld/attrs_1642510447205/work
certifi==2021.5.30
execnet==1.9.0
importlib-metadata @ file:///tmp/build/80754af9/importlib-metadata_1631916693255/work
iniconfig @ file:///home/linux1/recipes/ci/iniconfig_1610983019677/work
more-itertools @ file:///tmp/build/80754af9/more-itertools_1637733554872/work
packaging @ file:///tmp/build/80754af9/packaging_1637314298585/work
pluggy @ file:///tmp/build/80754af9/pluggy_1615976315926/work
py @ file:///opt/conda/conda-bld/py_1644396412707/work
-e git+https://github.com/ethereum/py_ecc.git@812722660d87c5c7366b1b4927dbf49a8ecbf3f9#egg=py_ecc
pyparsing @ file:///tmp/build/80754af9/pyparsing_1635766073266/work
pytest==6.2.4
pytest-xdist==3.0.2
toml @ file:///tmp/build/80754af9/toml_1616166611790/work
typing_extensions @ file:///opt/conda/conda-bld/typing_extensions_1647553014482/work
zipp @ file:///tmp/build/80754af9/zipp_1633618647012/work

name: py_ecc
channels:
  - defaults
  - https://repo.anaconda.com/pkgs/main
  - https://repo.anaconda.com/pkgs/r
  - conda-forge
dependencies:
  - _libgcc_mutex=0.1=main
  - _openmp_mutex=5.1=1_gnu
  - attrs=21.4.0=pyhd3eb1b0_0
  - ca-certificates=2025.2.25=h06a4308_0
  - certifi=2021.5.30=py36h06a4308_0
  - importlib-metadata=4.8.1=py36h06a4308_0
  - importlib_metadata=4.8.1=hd3eb1b0_0
  - iniconfig=1.1.1=pyhd3eb1b0_0
  - ld_impl_linux-64=2.40=h12ee557_0
  - libffi=3.3=he6710b0_2
  - libgcc-ng=11.2.0=h1234567_1
  - libgomp=11.2.0=h1234567_1
  - libstdcxx-ng=11.2.0=h1234567_1
  - more-itertools=8.12.0=pyhd3eb1b0_0
  - ncurses=6.4=h6a678d5_0
  - openssl=1.1.1w=h7f8727e_0
  - packaging=21.3=pyhd3eb1b0_0
  - pip=21.2.2=py36h06a4308_0
  - pluggy=0.13.1=py36h06a4308_0
  - py=1.11.0=pyhd3eb1b0_0
  - pyparsing=3.0.4=pyhd3eb1b0_0
  - pytest=6.2.4=py36h06a4308_2
  - python=3.6.13=h12debd9_1
  - readline=8.2=h5eee18b_0
  - setuptools=58.0.4=py36h06a4308_0
  - sqlite=3.45.3=h5eee18b_0
  - tk=8.6.14=h39e8969_0
  - toml=0.10.2=pyhd3eb1b0_0
  - typing_extensions=4.1.1=pyh06a4308_0
  - wheel=0.37.1=pyhd3eb1b0_0
  - xz=5.6.4=h5eee18b_1
  - zipp=3.6.0=pyhd3eb1b0_0
  - zlib=1.2.13=h5eee18b_1
  - pip:
      - execnet==1.9.0
      - pytest-xdist==3.0.2
prefix: /opt/conda/envs/py_ecc

tests/test_secp256k1.py::test_issue_4_bug
tests/test_secp256k1.py::test_privtopub tests/test_secp256k1.py::test_ecdsa_raw_sign
py_ecc/secp256k1/secp256k1.py
py_ecc/secp256k1/secp256k1.py