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Given the following text description, write Python code to implement the functionality described below step by step
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Description:
 For ecoinvent3.4 and ecoinvent3.5, the LCIA_implmentation.xls file does not include units for emissions of the pollutants anymore. This is a requirement however, in ecopold2matrix. This notebook introduces these units for emissions based on previous LCIA_implementation.xls files (e.g., based on ecoinvent3.3).
This notebook relies on pandas to import and manipulate data from excel and requires the user to have access to LCIA_implementation files for ecoinvent3.4 or 3.5 that they want to ready for ecospold2matrix, as well as an old LCIA_implementation_file.
Step1:  Pollutants which were already present in your old version will have their exchange unit introduced in the incomplete_LCIA. New pollutants of the recent LCIA_implementation file however, will still have NaN as their unit (i.e., no unit specified).
Step2:  Export the completed version of the LCIA_implmentation file where you want (e.g., in your ecoinvent folder with datasets and MasterData)
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Python Code:
import pandas as pd
old_LCIA = pd.read_excel('put_the_path_to_your_old_LCIA_implementation_file.xls_here','CFs')
incomplete_LCIA = pd.read_excel('put_the_path_to_your_incomplete_LCIA_implementation_file.xls_here','CFs')
complete_LCIA = incomplete_LCIA.merge(old_LCIA,how='left')
# drop obsolete columns
complete_LCIA = complete_LCIA.drop([i for i in old_LCIA.columns if i not in incomplete_LCIA.columns 
                                    and i != 'exchange unit'],axis=1)
Explanation: For ecoinvent3.4 and ecoinvent3.5, the LCIA_implmentation.xls file does not include units for emissions of the pollutants anymore. This is a requirement however, in ecopold2matrix. This notebook introduces these units for emissions based on previous LCIA_implementation.xls files (e.g., based on ecoinvent3.3).
This notebook relies on pandas to import and manipulate data from excel and requires the user to have access to LCIA_implementation files for ecoinvent3.4 or 3.5 that they want to ready for ecospold2matrix, as well as an old LCIA_implementation_file.
End of explanation
# m2*year for land use/land occupation categories
complete_LCIA.loc[[i for i in complete_LCIA.index if 'land' in complete_LCIA.category[i]
                 and type(complete_LCIA.loc[i,'exchange unit']) == float],'exchange unit'] = 'm2*year'
# kBq for pollutant linked to radioactivity
complete_LCIA.loc[[i for i in complete_LCIA.index if (complete_LCIA.category[i] == 'ionising radiation'
                   or complete_LCIA.category[i] == 'radioactive waste to deposit')
                   and type(complete_LCIA.loc[i,'exchange unit']) == float],'exchange unit'] = 'kBq'
# m3 for amounts of water
complete_LCIA.loc[[i for i in complete_LCIA.index if complete_LCIA.category[i] == 'water depletion'
                 and type(complete_LCIA.loc[i,'exchange unit']) == float],'exchange unit'] = 'm3'
# kg for the rest
complete_LCIA.loc[[i for i in complete_LCIA.index if type(complete_LCIA.loc[i,'exchange unit']) == float],
                  'exchange unit'] = 'kg'
Explanation: Pollutants which were already present in your old version will have their exchange unit introduced in the incomplete_LCIA. New pollutants of the recent LCIA_implementation file however, will still have NaN as their unit (i.e., no unit specified).
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complete_LCIA.to_excel('put_the_path_where_you_want_this_completed_version_to_be_stored.xls')
Explanation: Export the completed version of the LCIA_implmentation file where you want (e.g., in your ecoinvent folder with datasets and MasterData)
End of explanation
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