Stripping whitespaces from an xml element using ElementTree - python-3.x

Question

I'm having difficulty removing leading and trailing whitespace, even white space between elements that are deemed excessive. For the sake of the example, this is the xml document I'm currently running test cases on:
<?xml version="1.0"?>
<data>
<country name="Liechtenstein">
<rank>1</rank>
<year>2008</year>
<gdppc>141100</gdppc>
<neighbor name="Austria" direction="E"/>
<neighbor name="Switzerland" direction="W"/>
<description>Liechtenstein has a lot of flowers. </description>
</country>
<country name="Singapore">
<rank>4</rank>
<year>2011</year>
<gdppc>59900</gdppc>
<neighbor name="Malaysia" direction="N"/>
<description>Singapore has a lot of street markets.</description>
</country>
<country name="Panama">
<rank>68</rank>
<year>2011</year>
<gdppc>13600</gdppc>
<neighbor name="Costa Rica" direction="W"/>
<neighbor name="Colombia" direction="E"/>
<description> Panama has a lot of great food.</description>
</country>
</data>
Notice how in description for country name = "Liechtenstein" there is excess whitespace at the end of the description or excess white space between neighbor and description in the second country element or excess leading whitespace in description of the third country node.
Every time I run my code:
# Remove whitespace for each element in the tree
for elem in root.iter():
elem.text = elem.text.strip()
elem.tail = elem.tail.strip()
I end up with the following error:
AttributeError: 'NoneType' object has no attribute 'strip'

Answer 1

import xml.etree.ElementTree as ET
file = 'source.xml'
root = ET.parse(file)
for elem in root.iter():
if elem.text is not None:
elem.text = elem.text.strip()
if elem.tail is not None:
elem.tail = elem.tail.strip()
# print XML with stripped out whitespace
ET.dump(root)
# pretty print XML with stripped out whitespace
ET.indent(root, space="\t", level=0)
ET.dump(root)
Output (stripped out whitespace):
<data><country name="Liechtenstein"><rank>1</rank><year>2008</year><gdppc>141100</gdppc><neighbor name="Austria" direction="E" /><neighbor name="Switzerland" direction="W" /><description>Liechtenstein has a lot of flowers.</description></country><country name="Singapore"><rank>4</rank><year>2011</year><gdppc>59900</gdppc><neighbor name="Malaysia" direction="N" /><description>Singapore has a lot of street markets.</description></country><country name="Panama"><rank>68</rank><year>2011</year><gdppc>13600</gdppc><neighbor name="Costa Rica" direction="W" /><neighbor name="Colombia" direction="E" /><description>Panama has a lot of great food.</description></country></data>
Output (pretty-printed with stripped out whitespace):
<data>
<country name="Liechtenstein">
<rank>1</rank>
<year>2008</year>
<gdppc>141100</gdppc>
<neighbor name="Austria" direction="E" />
<neighbor name="Switzerland" direction="W" />
<description>Liechtenstein has a lot of flowers.</description>
</country>
<country name="Singapore">
<rank>4</rank>
<year>2011</year>
<gdppc>59900</gdppc>
<neighbor name="Malaysia" direction="N" />
<description>Singapore has a lot of street markets.</description>
</country>
<country name="Panama">
<rank>68</rank>
<year>2011</year>
<gdppc>13600</gdppc>
<neighbor name="Costa Rica" direction="W" />
<neighbor name="Colombia" direction="E" />
<description>Panama has a lot of great food.</description>
</country>
</data>