import xml.etree.ElementTree as ET

xml = """<?xml version="1.0" encoding="utf-8"?>
<pimp xmlns:dt="urn:schemas-microsoft-com:datatypes">
    <dllPath>C:\ReplayCode\Apps\Pimp</dllPath>
    <buffers>   
    <buffer name="InputMask">
            <width>5120</width>
            <height>3072</height>
            <data>UCHAR</data>
            <channels>1</channels>
            <type>IMG</type>
    </buffer>
    <buffer name="MaskErode">
            <width>5120</width>
            <height>3072</height>
            <data>UCHAR</data>
            <channels>1</channels>
            <type>IMG</type>
    </buffer>
    <buffer name="BlablaLutBla">
            <width>256</width>
            <height>256</height>
            <data>UCHAR</data>
            <channels>1</channels>
            <type>IMG</type>
    </buffer>
    <buffer name="MaskClose">
            <width>5120</width>
            <height>3072</height>
            <data>UCHAR</data>
            <channels>1</channels>
            <type>IMG</type>
    </buffer>
    <buffer name="InputVis">
            <width>5120</width>
            <height>3072</height>
            <data>UCHAR</data>
            <channels>3</channels>
            <type>IMG</type>
    </buffer>   
        <buffer name="AddMaskEdge">
            <width>5120</width>
            <height>3072</height>
            <data>UCHAR</data>
            <channels>1</channels>
            <type>IMG</type>
    </buffer>
    <buffer name="EdgeVis">
            <width>5120</width>
            <height>3072</height>
            <data>UCHAR</data>
            <channels>3</channels>
            <type>IMG</type>
    </buffer>       
        <buffer name="GrayEdge">
            <width>5120</width>
            <height>3072</height>
            <data>UCHAR</data>
            <channels>1</channels>
            <type>IMG</type>
    </buffer>
    <buffer name="EdgeMaskMulThreshold">
            <width>5120</width>
            <height>3072</height>
            <data>UCHAR</data>
            <channels>1</channels>
            <type>IMG</type>
    </buffer>
    <buffer name="MaskMulEdge">
            <width>5120</width>
            <height>3072</height>
            <data>UCHAR</data>
            <channels>1</channels>
            <type>IMG</type>
    </buffer>   
    </buffers>  
</pimp>
"""

root = ET.fromstring(xml)
for buffer in root.findall("buffers/buffer"): 
	if "Lut" in buffer.get("name"):
		buffer.set('type', 'MY_TYPE');
		buffer.find('width').text = "100"
		buffer[1].text = "125"

print ET.dump(root)