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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 from_ddy_file(cls, file_path):
 """Initalize from a ddy file object from an existing ddy file. args: file_path: A string representing a complete path to the .ddy file. """

        # check that the file is there
        if not os.path.isfile(file_path):
            raise ValueError(
                'Cannot find a .ddy file at {}'.format(file_path))
        if not file_path.lower().endswith('.ddy'):
            raise ValueError(
                'DDY file does not have a .ddy extension.')

        # check the python version and open the file
        try:
            iron_python = True if platform.python_implementation() == 'IronPython' \
                else False
        except Exception:
            iron_python = True

        if iron_python:
            ddywin = codecs.open(file_path, 'r')
        else:
            ddywin = codecs.open(file_path, 'r', encoding='utf-8', errors='ignore')

        try:
            ddytxt = ddywin.read()
            location_format = re.compile(
                r"(Site:Location,(.|\n)*?((;\s*!)|(;\s*\n)|(;\n)))")
            design_day_format = re.compile(
                r"(SizingPeriod:DesignDay,(.|\n)*?((;\s*!)|(;\s*\n)|(;\n)))")
            location_matches = location_format.findall(ddytxt)
            des_day_matches = design_day_format.findall(ddytxt)
        except Exception as e:
            import traceback
            raise Exception('{}\n{}'.format(e, traceback.format_exc()))
        else:
            # check to be sure location was found
            assert len(location_matches) > 0, 'No location objects found ' \
                'in .ddy file.'

            # build design day and location objects
            location = Location.from_location(location_matches[0][0])
            design_days = [DesignDay.from_ep_string(
                match[0], location) for match in des_day_matches]
        finally:
            ddywin.close()

        cls_ = cls(location, design_days)
        cls_._file_path = os.path.normpath(file_path)
        return cls_