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# Get filename here.fileitem = form['filename']# Test if the file was uploadedif fileitem.filename:# strip leading path from file name to avoid# directory traversal attacksfn = os.path.basename(fileitem.filename)open('/tmp/' + fn, 'wb').write(fileitem.file.read())message = 'The file "' + fn + '" was uploaded successfully'else:message = 'No file was uploaded'print """\Content-Type: text/html\n<html><body><p>%s</p></body></html>""" % (message,)If you are running above script on Unix/Linux, then you would have to take care of replacing file separator asfollows, otherwise on your windows machine above open() statement should work fine.fn = os.path.basename(fileitem.filename.replace("\\", "/" ))How To Raise a "File Download" Dialog Box? Sometimes, it is desired that you want to give option where a user will click a link and it will pop up a "FileDownload" dialogue box to the user instead of displaying actual content. This is very easy and will be achievedthrough HTTP header. This HTTP header will be different from the header mentioned in previous section.For example,if you want make a FileName file downloadable from a given link, then its syntax will be as follows:#!/usr/bin/python# HTTP Headerprint "Content-Type:application/octet-stream; name=\"FileName\"\r\n";print "Content-Disposition: attachment; filename=\"FileName\"\r\n\n";# Actual File Content will go hear.fo = open("foo.txt", "rb")str = fo.read();print str# Close opened filefo.close()Hope you enjoyed this tutorial. If yes, please send me your feedback at: Contact UsTUTORIALS POINT Simply Easy Learning
CHAPTER21Python Database AccessThe Python standard for database interfaces is the Python DB-API. Most Python database interfacesadhere to this standard.You can choose the right database for your application. Python Database API supports a wide range of databaseservers:• GadFly• mSQL• MySQL• PostgreSQL• Microsoft SQL Server 2000• Informix• Interbase• Oracle• SybaseHere is the list of available Python database interfaces: Python Database Interfaces and APIs .You mustdownload a separate DB API module for each database you need to access. For example, if you need to accessan Oracle database as well as a MySQL database, you must download both the Oracle and the MySQL databasemodules.The DB API provides a minimal standard for working with databases using Python structures and syntaxwherever possible. This API includes the following:• Importing the API module.• Acquiring a connection with the database.TUTORIALS POINT Simply Easy Learning
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Python Tutorial
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ABOUT THE TUTORIALPython TutorialPy
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Parameters ........................
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Locating Modules: .................
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Parameters ........................
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Description .......................
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Return Value ......................
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Example ...........................
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Parameters ........................
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Regular-expression Modifiers - Opti
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Starting a New Thread: ............
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Example: ..........................
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CHAPTER1Python OverviewPython is a
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CHAPTER2Python EnvironmentBefore we
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• To use this installer python-XY
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-c cmd run Python script sent in as
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This will produce the following res
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file_name = raw_input("Enter filena
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$ python -husage: python [option] .
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print 'Input file is "', inputfilep
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Here, an integer object is created
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Python Lists: Lists are the most v
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FunctionDescriptionint(x [,base])Co
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CHAPTER5Python Basic OperatorsWhat
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Line 4 - Value of c is 2Line 5 - Va
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Line 5 - a is greater than bLine 6
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| Binary OR Operator copies a bit i
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else:print "Line 3 - a and b are tr
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if ( id(a) == id(b) ):print "Line 2
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When you execute the above program,
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if statementsif...else statementsne
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Example: #!/usr/bin/pythonvar1 = 10
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else:print "Could not find true exp
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Loop Typewhile loopfor loopDescript
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num = raw_input("Enter a number :")
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Good bye!Iterating by Sequence I
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11 is prime13 is prime17 is prime19
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continue statement The continue st
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CHAPTER8Python NumbersNumber data t
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max(x1, x2,...)min(x1, x2,...)modf(
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Syntax Following is the syntax for
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import math# This will import math
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import mathmath.log10( x )Note: Thi
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modf(x) Description The method modf
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round( x [, n] )Parameters • x --
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Return Value This method returns a
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seed([x]) Description The method se
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asin(x)Note: This function is not a
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print "atan2(-10,10) : ", math.atan
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Note: This function is not accessib
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import mathprint "degrees(3) : ", m
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CHAPTER9Python StringsStrings are a
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+ Concatenation - Adds values on ei
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TAB ( \t ) and they will show up th
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str = "this is string example....wo
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Return Value This method returns a
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Description The method expandtabs()
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Traceback (most recent call last):F
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Let us compile and run the above pr
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str = "This is string example....wo
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str = "-";seq = ("a", "b", "c"); #
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lstrip() Description The method lst
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Max character: xmin(str) Descriptio
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str = "this is really a string exam
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Parameters • chars -- You can sup
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Parameters• str -- This is the st
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Parameters • NAReturn Value This
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Example The following example shows
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CHAPTER10Python ListsThe most basic
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Python Expression Results Descripti
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list( seq )Parameters • seq -- Th
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Return Value If elements are of th
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list.insert(index, obj)Parameters
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CHAPTER11Python TuplesAtuple is a s
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len((1, 2, 3)) 3 Length(1, 2, 3) +
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-11-1len(tuple) Description The met
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min value element : 200tuple(seq) D
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#!/usr/bin/pythondict = {'Name': 'Z
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34str(dict)Produces a printable str
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type(variable) Description The meth
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Return Value This method does not
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CHAPTER13Python Date & TimeApython
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#!/usr/bin/pythonimport time;localt
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import timeprint "time.altzone %d "
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Parameters • sec -- These are the
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• %w - day of the week as a decim
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time.time( ) Description The metho
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2time.tznameAttribute time.tzname i
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CHAPTER14Python FunctionAfunction i
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#!/usr/bin/python# Function definit
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return;# Now you can call printinfo
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Inside the function : 30Outside the
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A module is loaded only once, regar
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'sqrt', 'tan', 'tanh']Here, the spe
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CHAPTER16Python Files I/OThis chapt
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rb+WWbw+wb+AAba+ab+Opens a file for
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fo.write( "Python is a great langua
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EXAMPLE: Following is the example t
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operations from the operating syste
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# Close opened filefo.close()Let us
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Parameters • NAReturn Value This
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Parameters • offset -- This is th
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Parameters • size -- If this opti
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Description The method writelines()
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53545556575859606162os.symlink(src,
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• stat.S_IRGRP: Read by group.•
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os.chroot("/tmp/usr")print "Changed
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Parameters • fd -- This is the or
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import os, sys# First go to the "/v
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Description The method fchown() cha
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Description The method fdopen() ret
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{'PC_MAX_INPUT': 2, 'PC_VDISABLE':
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# Open a filefd = os.open( "foo.txt
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print "Current working dir : %s" %
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path = "/var/www/html/foo.txt"fd =
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_vti_txtrobots.txtitemlistingresume
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# Close opened fileos.close( fd )#
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dev_num = os.makedev(major_dnum, mi
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-rw-------. 1 root root 0 Apr 30 02
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os.pathconf(path, name) Descriptio
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Description The method popen() open
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# !/usr/bin/pythonimport ossrc = '/
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Page 293 and 294: Description The method tcgetpgrp()
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Page 309 and 310: self.args = argSo once you defined
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Page 315 and 316: print 'Calling child method'c = Chi
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Page 327 and 328: CHAPTER20Python CGI ProgrammingWhat
Page 329 and 330: If you click hello.py, then this pr
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Page 345 and 346: DELETE Operation: DELETE operation
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Page 353 and 354: Subject: SMTP e-mail testThis is a
Page 355 and 356: try:smtpObj = smtplib.SMTP('localho
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Page 369 and 370: Tkinter Widgets Tkinter provides v
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Page 379 and 380: E1 = Entry(top, bd =5)E1.pack(side
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filemenu.add_command(label="Exit",
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Example: Try the following example
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WidthWraplengthWidth of the label i
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label appears in the top left corne
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Parameters: • master: This repres
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Parameters: • master: This repres
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mark_gravity(mark [,gravity])Return
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Methods & Descriptiondeiconify()Dis
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disabledbackgrounddisabledforegroun
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bgbdThe color of the slider and arr
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fontheightlabelAnchorhighlightbackg
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Standard attributes:Let's take a l
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• family: The font family name as
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B2.pack()B3.pack()B4.pack()B5.pack(
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• "heart"• "heart"• "man"•
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The grid() Method This geometry m
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CHAPTERPython Further Extensions27A
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This table needs to be terminated w
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Passing Function Parameters: Beca
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return (a + b)You can return two va
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CHAPTER28Python Tools/UtilitiesThe
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The profile Module: The profile m
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