class NumberWordFormatter:
    """
    This is a class that provides to convert numbers into their corresponding English word representation, including handling the conversion of both the integer and decimal parts, and incorporating appropriate connectors and units.
    """
    def __init__(self):
        self.NUMBER = ["", "ONE", "TWO", "THREE", "FOUR", "FIVE", "SIX", "SEVEN", "EIGHT", "NINE"]
        self.NUMBER_TEEN = ["TEN", "ELEVEN", "TWELVE", "THIRTEEN", "FOURTEEN", "FIFTEEN", "SIXTEEN", "SEVENTEEN",
                            "EIGHTEEN",
                            "NINETEEN"]
        self.NUMBER_TEN = ["TEN", "TWENTY", "THIRTY", "FORTY", "FIFTY", "SIXTY", "SEVENTY", "EIGHTY", "NINETY"]
        self.NUMBER_MORE = ["", "THOUSAND", "MILLION", "BILLION"]
        self.NUMBER_SUFFIX = ["k", "w", "", "m", "", "", "b", "", "", "t", "", "", "p", "", "", "e"]

    def format(self, x):
        """
        Converts a number into words format
        :param x: int or float, the number to be converted into words format
        :return: str, the number in words format
        >>> formatter = NumberWordFormatter()
        >>> formatter.format(123456)
        "ONE HUNDRED AND TWENTY THREE THOUSAND FOUR HUNDRED AND FIFTY SIX ONLY"
        """

        if x is not None:
            return self.format_string(str(x))
        else:
            return ""

    def format_string(self, x):
        """
        Converts a string representation of a number into words format
        :param x: str, the string representation of a number
        :return: str, the number in words format
        >>> formatter = NumberWordFormatter()
        >>> formatter.format_string("123456")
        "ONE HUNDRED AND TWENTY THREE THOUSAND FOUR HUNDRED AND FIFTY SIX ONLY"
        """

        lstr, rstr = (x.split('.') + [''])[:2]
        lstrrev = lstr[::-1]
        a = [''] * 5

        if len(lstrrev) % 3 == 1:
            lstrrev += "00"
        elif len(lstrrev) % 3 == 2:
            lstrrev += "0"

        lm = ""
        for i in range(len(lstrrev) // 3):
            a[i] = lstrrev[3 * i:3 * i + 3][::-1]
            if a[i] != "000":
                lm = self.trans_three(a[i]) + " " + self.parse_more(i) + " " + lm
            else:
                lm += self.trans_three(a[i])

        xs = f"AND CENTS {self.trans_two(rstr)} " if rstr else ""
        if not lm.strip():
            return "ZERO ONLY"
        else:
            return f"{lm.strip()} {xs}ONLY"

    def trans_two(self, s):
        """
        Converts a two-digit number into words format
        :param s: str, the two-digit number
        :return: str, the number in words format
        >>> formatter = NumberWordFormatter()
        >>> formatter.trans_two("23")
        "TWENTY THREE"
        """

        s = s.zfill(2)
        if s[0] == "0":
            return self.NUMBER[int(s[-1])]
        elif s[0] == "1":
            return self.NUMBER_TEEN[int(s) - 10]
        elif s[1] == "0":
            return self.NUMBER_TEN[int(s[0]) - 1]
        else:
            return self.NUMBER_TEN[int(s[0]) - 1] + " " + self.NUMBER[int(s[-1])]

    def trans_three(self, s):
        """
        Converts a three-digit number into words format
        :param s: str, the three-digit number
        :return: str, the number in words format
        >>> formatter = NumberWordFormatter()
        >>> formatter.trans_three("123")
        "ONE HUNDRED AND TWENTY THREE"
        """

        if s[0] == "0":
            return self.trans_two(s[1:])
        elif s[1:] == "00":
            return f"{self.NUMBER[int(s[0])]} HUNDRED"
        else:
            return f"{self.NUMBER[int(s[0])]} HUNDRED AND {self.trans_two(s[1:])}"

    def parse_more(self, i):
        return self.NUMBER_MORE[i]

Method:
def parse_more(self, i):
        return self.NUMBER_MORE[i]

Summary: Parses the thousand/million/billion suffix based on the index