[' '' '' ' [ [anx [[' '' '' '][ ] [ [' '' '' ' [ ][ ' first steps towards programming of coursewe can use python for more complicated tasks than adding two and two together for instancewe can write an initial sub-sequence of the fibonacci series as followsfibonacci seriesthe sum of two elements defines the next ab while print(aab ba+ this example introduces several new features the first line contains multiple assignmentthe variables and simultaneously get the new values and on the last line this is used againdemonstrating that the expressions on the right-hand side are all evaluated first before any of the assignments take place the right-hand side expressions are evaluated from the left to the right the while loop executes as long as the condition (herea remains true in pythonlike in cany non-zero integer value is truezero is false the condition may also be string or list valuein fact any sequenceanything with non-zero length is trueempty sequences are false the test used in the example is simple comparison the standard comparison operators are written the same as in (greater than)=(equal to)(greater than or equal toand !(not equal tothe body of the loop is indentedindentation is python' way of grouping statements at the interactive promptyou have to type tab or space(sfor each indented line in practice you will prepare more complicated input for python with text editorall decent text editors have an auto-indent facility when compound statement is entered interactivelyit must be followed by blank line to indicate completion (since the parser cannot guess when you have typed the last linenote that each line within basic block must be indented by the same amount the print(function writes the value of the argument(sit is given it differs from just writing the expression you want to write (as we did earlier in the calculator examplesin the way it handles multiple argumentsfloating point quantitiesand strings strings are printed without quotesand space is inserted between itemsso you can format things nicelylike this an informal introduction to python