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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def dump(self, tofile=None, width=16, withpadding=False):
 """Dump object content to specified file object or to stdout if None. Format is a hexdump with some header information at the beginning, addresses on the left, and data on right. @param tofile file-like object to dump to @param width number of bytes per line (i.e. columns) @param withpadding print padding character instead of '--' @raise ValueError if width is not a positive integer """


        if not isinstance(width,int) or width < 1:
            raise ValueError('width must be a positive integer.')
        # The integer can be of float type - does not work with bit operations
        width = int(width)
        if tofile is None:
            tofile = sys.stdout

        # start addr possibly
        if self.start_addr is not None:
            cs = self.start_addr.get('CS')
            ip = self.start_addr.get('IP')
            eip = self.start_addr.get('EIP')
            if eip is not None and cs is None and ip is None:
                tofile.write('EIP = 0x%08X\n' % eip)
            elif eip is None and cs is not None and ip is not None:
                tofile.write('CS = 0x%04X, IP = 0x%04X\n' % (cs, ip))
            else:
                tofile.write('start_addr = %r\n' % start_addr)
        # actual data
        addresses = dict_keys(self._buf)
        if addresses:
            addresses.sort()
            minaddr = addresses[0]
            maxaddr = addresses[-1]
            startaddr = (minaddr // width) * width
            endaddr = ((maxaddr // width) + 1) * width
            maxdigits = max(len(hex(endaddr)) - 2, 4)   # Less 2 to exclude '0x'
            templa = '%%0%dX' % maxdigits
            rangewidth = range_l(width)
            if withpadding:
                pad = self.padding
            else:
                pad = None
            for i in range_g(startaddr, endaddr, width):
                tofile.write(templa % i)
                tofile.write(' ')
                s = []
                for j in rangewidth:
                    x = self._buf.get(i+j, pad)
                    if x is not None:
                        tofile.write(' %02X' % x)
                        if 32 <= x < 127:   # GNU less does not like 0x7F (128 decimal) so we'd better show it as dot
                            s.append(chr(x))
                        else:
                            s.append('.')
                    else:
                        tofile.write(' --')
                        s.append(' ')
                tofile.write('  |' + ''.join(s) + '|\n')