def getrequest(url, header):

    try:
        r = requests.get(url, headers=header)
        r.raise_for_status()
        return r
    except requests.exceptions.RequestException as e:
        print(e)
        sys.exit(1)


# ========================
# Pytest

def test_function():
    url = 'someurl'
    myresult = getrequest(url, build_headers()).text
    # asserts here
    # ...