Checks if given section exists.

        Usage::

            >>> content = ["[Section A]\\n", "; Comment.\\n", "Attribute 1 = \\"Value A\\"\\n", "\\n", \
"[Section B]\\n", "Attribute 2 = \\"Value B\\"\\n"]
            >>> sections_file_parser = SectionsFileParser()
            >>> sections_file_parser.content = content
            >>> sections_file_parser.parse()
            <foundations.parsers.SectionsFileParser object at 0x845683844>
            >>> sections_file_parser.section_exists("Section A")
            True
            >>> sections_file_parser.section_exists("Section C")
            False

        :param section: Section to check existence.
        :type section: unicode
        :return: Section existence.
        :rtype: bool

def section_exists(self, section):
        """
        Checks if given section exists.

        Usage::

            >>> content = ["[Section A]\\n", "; Comment.\\n", "Attribute 1 = \\"Value A\\"\\n", "\\n", \
"[Section B]\\n", "Attribute 2 = \\"Value B\\"\\n"]
            >>> sections_file_parser = SectionsFileParser()
            >>> sections_file_parser.content = content
            >>> sections_file_parser.parse()
            <foundations.parsers.SectionsFileParser object at 0x845683844>
            >>> sections_file_parser.section_exists("Section A")
            True
            >>> sections_file_parser.section_exists("Section C")
            False

        :param section: Section to check existence.
        :type section: unicode
        :return: Section existence.
        :rtype: bool
        """

        if section in self.__sections:
            LOGGER.debug("> '{0}' section exists in '{1}'.".format(section, self))
            return True
        else:
            LOGGER.debug("> '{0}' section doesn't exists in '{1}'.".format(section, self))
            return False