Merge 0de5e8fef1 into d143c60246

swap current line with previous

languages/bash.sh

@@ -47,9 +47,10 @@ CTRL+X then )   # finish recording keyboard macro
 CTRL+X then E   # recall last recorded keyboard macro
 CTRL+X then CTRL+E   # invoke text editor (specified by $EDITOR) on current command line then execute resultes as shell commands
 CTRL+A then D  # logout from screen but don't kill it, if any command exist, it will continue 
-
-BACKSPACE  # deletes one character backward
-DELETE     # deletes one character under cursor
+CTRL+T then Z # Minimizes the current session or sends the current session to the background.
+fg(foreground) # Maxmizes the current session 
+BACKSPACE      # deletes one character backward
+DELETE         # deletes one character under cursor
 
 history   # shows command line history
 !!        # repeats the last command

languages/python.md

@@ -380,3 +380,14 @@ function_name()
 * We need not to specify the return type of the function.
 * Functions by default return `None` 
 * We can return any datatype.
+### f strings
+* Short of "formatted string".
+* Allow us to to embed expressions inside string literals.
+* f-strings are denoted by "f" or "F" prefix before the string
+* Expressions are closed by curly braces '{}' with the f-string
+```
+name = "Alice"
+print(f"Hello, I am {name} and I am a programmer.")
+
+```
+	

tools/vim.txt

@@ -105,7 +105,7 @@ gu$                 make lowercase until end of line
 <<                  indent line one column to left
 ==                  auto-indent current line
 ddp                 swap current line with next
-ddkp                swap current line with previous
+ddkP                swap current line with previous
 :%retab             fix spaces / tabs issues in whole file
 :r [name]           insert the file [name] below the cursor.
 :r !{cmd}           execute {cmd} and insert its standard output below the cursor.