<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def ipinfo_ip_check(ip):
 """Checks ipinfo.io for basic WHOIS-type data on an IP address"""

    if not is_IPv4Address(ip):
        return None

    response = requests.get('http://ipinfo.io/%s/json' % ip)
    return response.json()