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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 _get_value_and_line_offset(self, key, values):
 """Returns the index of the location of key, value pair in lines. :type key: str :param key: key, in config file. :type values: str :param values: values for key, in config file. This is plural, because you can have multiple values per key. e.g. :type lines: list :param lines: a collection of lines-so-far in file :rtype: list(tuple) """

        values_list = self._construct_values_list(values)
        if not values_list:
            return []

        current_value_list_index = 0
        output = []
        lines_modified = False

        for index, line in enumerate(self.lines):
            # Check ignored lines before checking values, because
            # you can write comments *after* the value.
            if not line.strip() or self._comment_regex.match(line):
                continue

            if (
                self.exclude_lines_regex and
                self.exclude_lines_regex.search(line)
            ):
                continue

            if current_value_list_index == 0:
                first_line_regex = re.compile(r'^\s*{}[ :=]+{}'.format(
                    re.escape(key),
                    re.escape(values_list[current_value_list_index]),
                ))
                if first_line_regex.match(line):
                    output.append((
                        values_list[current_value_list_index],
                        self.line_offset + index + 1,
                    ))
                    current_value_list_index += 1
                continue

            if current_value_list_index == len(values_list):
                if index == 0:
                    index = 1  # don't want to count the same line again
                self.line_offset += index
                self.lines = self.lines[index:]
                lines_modified = True
                break
            else:
                output.append((
                    values_list[current_value_list_index],
                    self.line_offset + index + 1,
                ))

                current_value_list_index += 1

        if not lines_modified:
            # No more lines left, if loop was not explicitly left.
            self.lines = []

        return output