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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 _format_grndt(self, data_c):
 """Format monthly ground data collection into string for the EPW header."""

        monthly_str = '{},{},{},{}'.format(
            data_c.header.metadata['soil conductivity'],
            data_c.header.metadata['soil density'],
            data_c.header.metadata['soil specific heat'],
            ','.join(['%.2f' % x for x in data_c.values]))
        return monthly_str