Requirements fix.

requirements.txt

 sqlalchemy==1.3.13
 Flask==1.1.1
-Flask-Caching=1.8.0
+Flask-Caching==1.8.0
 Flask-SQLAlchemy==2.4.1
 Flask-RESTful==0.3.8
 flask-marshmallow==0.11.0
@@ -16,4 +16,4 @@ simplejson==3.17.0
 accessify==0.3.1
 librosa==0.7.2
 gunicorn==20.0.4
-pyyaml-5.3.1
\ No newline at end of file
+pyyaml==5.3.1
\ No newline at end of file