@classmethod<EOL><INDENT>def _convert_to_style(cls, style_dict, num_format_str=None):<DEDENT>
import xlwt<EOL>if style_dict:<EOL><INDENT>xlwt_stylestr = cls._style_to_xlwt(style_dict)<EOL>style = xlwt.easyxf(xlwt_stylestr, field_sep='<STR_LIT:U+002C>', line_sep='<STR_LIT:;>')<EOL><DEDENT>else:<EOL><INDENT>style = xlwt.XFStyle()<EOL><DEDENT>if num_format_str is not None:<EOL><INDENT>style.num_format_str = num_format_str<EOL><DEDENT>return style<EOL>
converts a style_dict to an xlwt style object
Parameters
----------
style_dict : style dictionary to convert
num_format_str : optional number format string