Update README.md

Author: eduard93

README.md

@@ -1,2 +1,25 @@
 # PythonAdapter
-Python adapter via callout for InterSystems Data Platform
+Python adapter via callout for InterSystems Data Platforms.
+
+# Installation
+
+1. Load ObjectScript code from [here](https://github.com/intersystems-ru/PythonAdapter/blob/master/isc/py/Callout.cls).
+2. Place DLLs in `bin` folder.
+
+# Use
+
+```
+do ##class(isc.py.Callout).Initialize()
+write ##class(isc.py.Callout).SimpleString("x='ПРИВЕТ'","x")
+write ##class(isc.py.Callout).SimpleString("x=repr('ПРИВЕТ')","x")
+write ##class(isc.py.Callout).SimpleString("x=123","x")
+write ##class(isc.py.Callout).Unload()
+```
+
+
+# Development
+
+Development of ObjectScript is done via [cache-tort-git](https://github.com/MakarovS96/cache-tort-git) in UDL mode. 
+Development of C code is done in Eclipse.
+
+