I need some help using Python in order to extract from a txt file a particular part.
Indeed, I would like from the following file to extract only the part with `Organism :` 
But without keeping the part between the "`()`".

In this exemple it would give: 

```
Select item 1949871
1.

Amel_HAv3.1

Organism:
    Apis mellifera (honey bee)

Infraspecific name:
    Strain: DH4

Sex:
    male

Submitter:
    Uppsala University

Date:
    2018/09/10

Assembly level:
    Chromosome

Genome representation:
    full

RefSeq category:
    representative genome

GenBank assembly accession:
    GCA_003254395.2 (latest) 

RefSeq assembly accession:
    GCF_003254395.2 (latest) 

IDs:
    1949871 [UID] 7372188 [GenBank] 7434688 [RefSeq]

Select item 2027291
2.

Obir_v5.4

Organism:
    Ooceraea biroi (clonal raider ant)

Submitter:
    The Rockefeller University

Date:
    2018/10/23

Assembly level:
    Chromosome

Genome representation:
    full

RefSeq category:
    representative genome

GenBank assembly accession:
    GCA_003672135.1 (latest) 

RefSeq assembly accession:
    GCF_003672135.1 (latest) 

IDs:
    2027291 [UID] 7620928 [GenBank] 7654158 [RefSeq]

Select item 1769491
3.

Nlec1.1

Organism:
    Neodiprion lecontei (redheaded pine sawfly)

Sex:
    male

Submitter:
    University of Kentucky

Date:
    2018/06/21

Assembly level:
    Chromosome

Genome representation:
    full

RefSeq category:
    representative genome

GenBank assembly accession:
    GCA_001263575.2 (latest) 

RefSeq assembly accession:
    n/a

IDs:
    1769491 [UID] 6705508 [GenBank] 

Select item 294348
4.

Bter_1.0

```

and I would like in python to only keep the part after Organism: (without the part between "`()`") and get for this exemple: 

```
Apis mellifera
Neodiprion lecontei
Ooceraea biroi

```

Does someone have an idea please? 

Thank you for your help.