code: def get_records_for_code(self, meth_code, incl=True, use_slice=False,
                               sli=None, strict_match=True):
          
          # (must use fillna to replace np.nan with False for indexing)
          if use_slice:
              df = sli.copy()
          else:
              df = self.df.copy()
          # if meth_code not provided, return unchanged dataframe
          if not meth_code:
              return df
          # get regex
          if not strict_match:
              # grab any record that contains any part of meth_code
              cond = df['method_codes'].str.contains(meth_code).fillna(False)
          else:
              # grab only an exact match
              pattern = re.compile('{}(?=:|\s|\Z)'.format(meth_code))
              cond = df['method_codes'].str.contains(pattern).fillna(False)
          if incl:
              # return a copy of records with that method code:
              return df[cond]
          else:
              # return a copy of records without that method code
              return df[~cond]
docs: Use regex to see if meth_code is in the method_codes ":" delimited list.
          If incl == True, return all records WITH meth_code.
          If incl == False, return all records WITHOUT meth_code.
          If strict_match == True, return only records with the exact meth_code.
          If strict_match == False, return records that contain the meth_code partial string,
          (i.e., "DE-").
          Not inplace