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<FONT><h3><tt cLASS="monofont">copy</tt></h3>
<p>The <TT CLass="monofont">copy</tT> module provides shallow and deep object copying operations for lists, tuples, dictionaries, and class instances.</P>
<H4><Tt class="monofont">copy.copy()</tt></h4>
<p>This function creates a shallow copy of the <tt class="monofont">x</tt> object.</p>
<Pre>
>>> import copy
>>> x = [1, 2, 3, [4, 5, 6]]
>>> y = copy.copy(x)
>>> print y
[1, 2, 3, [4, 5, 6]]
>>> id(y) == id(x)
0
</Pre>
<p>As you can see at the end of the previous example, the new list is not the old one.</P>
<p>As you can see, this function provides the same result that <tt cLass="monofont">y=x[:]</TT> does. It creates a new object that references the old one. If the original object is a mutable object and has its value changed, the new object will change too.</P>
<H4><tt clASS="monofont">copy.deepcopy()</Tt></h4>
<p>It recursively copies the entire object. It really creates a new object without any link to the original structure.</p>
<P><A NAme="idx1073742716"></a>basic syntax: <tT CLAss="monofont">variable = copy.deepcopy(</tt><i><tt class="monofont">object</tt></i><tt claSs="monofont">)<a Name="idx1073742717"></A><a namE="idx1073742718"></a></tt></P>
<PRE>
>>> import copy
>>> listone = [{ "name":"Andre"} , 3, 2]
>>> listtwo = copy.copy(listone)
>>> listthree = copy.deepcopy(listone)
>>> listone[0]["name"] = "Renata"
>>> listone.append("Python")
>>> print listone, listtwo, listthree
[{ "name":"Renata"} , 3, 2, "Python"]
[{ "name":"Renata"} , 3, 2]
[{ "name":"Andre} , 3, 2]
</pre>
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<P><TABLE width="100%" border=0><TR valign="top"><TD><font size=1 color="#C0C0C0"><br></font></TD><TD align=right><font size=1 color="#C0C0C0">Last updated on 1/30/2002<br>Python Developer's Handbook, © 2002 Sams Publishing</font></TD></TR></TABLE></P>
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<br><TABLE width=100% bgcolor=white border=0 cellspacing=0 cellpadding=5><TR><TD><H4 class=Title>Index terms contained in this section</H4>
<font size=2>
libraries<BR>
<a href="#idx1073742717">Python Services</a><BR>
<a href="#idx1073742718">Python Services</a><BR>
syntax<BR>
functions<BR>
<a href="#idx1073742716">copy.deepcopy()</a><BR>
<BR>
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