update README and fix flake8

README.md

 # Metagenedb
 
-[![pipeline status](https://gitlab.pasteur.fr/metagenomics/metagenedb/badges/master/pipeline.svg)](https://gitlab.pasteur.fr/metagenomics/metagenedb/commits/dev)
-[![coverage report](https://gitlab.pasteur.fr/metagenomics/metagenedb/badges/master/coverage.svg)](https://gitlab.pasteur.fr/metagenomics/metagenedb/commits/dev)
+[![pipeline status](https://gitlab.pasteur.fr/%{project_path}/badges/%{default_branch}/pipeline.svg)](https://gitlab.pasteur.fr/%{project_path}/commits/%{default_branch})
+[![coverage report](https://gitlab.pasteur.fr/%{project_path}/badges/%{default_branch}/coverage.svg)](https://gitlab.pasteur.fr/%{project_path}/commits/%{default_branch})
 
 Django based project to build genes catalog and tools
 to play with it and contact external services.

backend/metagenedb/apps/catalog/models/gene.py

@@ -20,6 +20,7 @@ class Gene(models.Model):
     class Meta:
         ordering = ['-gene_id']
 
+
 class GeneFunction(models.Model):
     gene = models.ForeignKey(Gene, on_delete=models.CASCADE)
     function = models.ForeignKey(Function, on_delete=models.CASCADE)

backend/metagenedb/apps/catalog/serializers/gene.py

@@ -16,6 +16,10 @@ class GeneListSerializer(BulkListSerializer):
     class Meta:
         model = Gene
 
+    def create(self, validated_data):
+        instances = super().create(validated_data)
+        return instances
+
 
 class GeneSerializer(serializers.ModelSerializer):
     functions = FunctionSerializer(