def __init__(self, address, strict=True):

        """Instantiate a new IPv4 network object.

        Args:
            address: A string or integer representing the IP [& network].
              '192.0.2.0/24'
              '192.0.2.0/255.255.255.0'
              '192.0.0.2/0.0.0.255'
              are all functionally the same in IPv4. Similarly,
              '192.0.2.1'
              '192.0.2.1/255.255.255.255'
              '192.0.2.1/32'
              are also functionally equivalent. That is to say, failing to
              provide a subnetmask will create an object with a mask of /32.

              If the mask (portion after the / in the argument) is given in
              dotted quad form, it is treated as a netmask if it starts with a
              non-zero field (e.g. /255.0.0.0 == /8) and as a hostmask if it
              starts with a zero field (e.g. 0.255.255.255 == /8), with the
              single exception of an all-zero mask which is treated as a
              netmask == /0. If no mask is given, a default of /32 is used.

              Additionally, an integer can be passed, so
              IPv4Network('192.0.2.1') == IPv4Network(3221225985)
              or, more generally
              IPv4Interface(int(IPv4Interface('192.0.2.1'))) ==
                IPv4Interface('192.0.2.1')

        Raises:
            AddressValueError: If ipaddress isn't a valid IPv4 address.
            NetmaskValueError: If the netmask isn't valid for
              an IPv4 address.
            ValueError: If strict is True and a network address is not
              supplied.

        """

        _BaseV4.__init__(self, address)
        _BaseNetwork.__init__(self, address)

        # Constructing from a packed address
        if isinstance(address, bytes):
            self.network_address = IPv4Address(address)
            self._prefixlen = self._max_prefixlen
            self.netmask = IPv4Address(self._ALL_ONES)
            #fixme: address/network test here
            return

        # Efficient constructor from integer.
        if isinstance(address, int):
            self.network_address = IPv4Address(address)
            self._prefixlen = self._max_prefixlen
            self.netmask = IPv4Address(self._ALL_ONES)
            #fixme: address/network test here.
            return

        # Assume input argument to be string or any object representation
        # which converts into a formatted IP prefix string.
        addr = _split_optional_netmask(address)
        self.network_address = IPv4Address(self._ip_int_from_string(addr[0]))

        if len(addr) == 2:
            try:
                # Check for a netmask in prefix length form
                self._prefixlen = self._prefix_from_prefix_string(addr[1])
            except NetmaskValueError:
                # Check for a netmask or hostmask in dotted-quad form.
                # This may raise NetmaskValueError.
                self._prefixlen = self._prefix_from_ip_string(addr[1])
        else:
            self._prefixlen = self._max_prefixlen
        self.netmask = IPv4Address(self._ip_int_from_prefix(self._prefixlen))

        if strict:
            if (IPv4Address(int(self.network_address) & int(self.netmask)) !=
                self.network_address):
                raise ValueError('%s has host bits set' % self)
        self.network_address = IPv4Address(int(self.network_address) &
                                           int(self.netmask))

        if self._prefixlen == (self._max_prefixlen - 1):
            self.hosts = self.__iter__
dataset/ETHPy150Open saltstack/salt/salt/ext/ipaddress.py/IPv4Network.__init__/original