added functions key_to_table_key & key_to_context_key to common server python (#1965)
added functions key_to_table_key & key_to_context_key to common server python (#1965)

* added functions key_to_table_key & key_to_context_key

* few changes to the key_to_table & key_to_context

* changed names to the string_to_table & string_to_context

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