def check_ipv4(ip_str):
    """
    Return True if is a valid IP v4
    """
    try:
        socket.inet_pton(socket.AF_INET, ip_str)
    except AttributeError:
        try:
            socket.inet_aton(ip_str)
        except socket.error:
            return False
        return ip_str.count('.') == 3
    except socket.error:
        return False
    return True
Return True if is a valid IP v4