First of all, thank you for the seniors who tried to help me.

I’ve a large XML file (below is an example with 2 parents).
Each parent(U7418、U2501) might have subchild、subsubchild…etc like parent U2501 below.

<CircuitRoot Title="projectname" Creator="Lee" Date="2020-08-27">
  <Profile Platform="SeriesName" />
  <U7418 PartNumber="084.21321" Footprint="PPAK-8P" Value="AONR21321" Description="FET MOS AONR21321 PC DFN 3X3 EP 8P">
    <U7418 PartNumber="084.21321" Footprint="PPAK-8P" Ball="4" Pin="G" Page="74" Net="LPS_SW">
      <R7403 PartNumber="ZZ.R0402" Info="0R-PAD" Net="GND">
        <Q7408 PartNumber="084.03413" Pin="D" />
      </R7403>
      <R7402 PartNumber="64.20035" Net="LPS_SW_A">
        <Q7406 PartNumber="075.00138" Pin="D2" />
      </R7402>
      <C7401 PartNumber="78.15224" Power="+SDC_IN" />
    </U7418>
    <U7418 PartNumber="084.21321" Footprint="PPAK" Ball="3" Pin="S#3" Page="74" Power="+SDC_IN" />
  </U7418>
  <U2501 PartNumber="072.25Q64" Footprint="SOIC8" Value="W25Q64JVSSIQ" Description="IC FLASH">
    <U2501 PartNumber="072.25Q64" Footprint="SOIC8" Ball="1" Pin="CS#" Page="25" Net="SPI_CS_ROM_N0">
      <R2501 PartNumber="63.47234" Power="3D3V_SPI" />
      <R2403 PartNumber="ZZ.R0402" Net="SHD_CS0#">
        <U2401 PartNumber="071.01515" Pin="GPIO055/PWM2/SHD_CS0#/BSS_STRAP" />
        <R2405 PartNumber="63.R0034" Remark="[email protected]" Net="PCH_RSMRST#">
          <R2404 PartNumber="ZZ.R0402" Net="PCH_RSMRST#_R">
            <U2401 PartNumber="071.01515" Pin="GPIO114/PS2_CLK0A/EC_SCI#" />
          </R2404>
          <TP2401 PartNumber="ZZ.PAD14" Pin="1" />
          <R1709 PartNumber="63.10234" Net="PM_RSMRST#">
            <Q1701 PartNumber="75.27002" Pin="3" />
            <CPU1 PartNumber="ZZ.00CPU" Pin="RSMRST#" />
            <R6414 PartNumber="64.33035L" Net="M_BIST">
              <Q6408 PartNumber="84.T3904" Pin="B" />
              <U2401 PartNumber="071.01515" Pin="GPIO246/CMP_VREF0" />
              <D6403 PartNumber="83.R2003" Net="GND">
                <PG4408 PartNumber="ZZ.CLOSE" Net="PWR_CHG_ACOK">
                  <PU4401 PartNumber="074.09538" Pin="ACOK" />
                  <PR4426 PartNumber="64.19635" Power="GND" />
                </PG4408>
                <U2401 PartNumber="071.01515" Pin="VCI_OVRD_IN/GPIO172" />
              </D6403>
              <C6405 PartNumber="78.10523" Power="GND" />
            </R6414>
          </R1709>
        </R2405>
      </R2403>
      <R1832 PartNumber="ZZ.R0402" Net="SPI">
        <CPU1 PartNumber="ZZ.00CPU" Pin="SPI0_CS0#" />
      </R1832>
    </U2501>
    <U2501 PartNumber="072.25Q64" Footprint="SOIC8" Power="3D3V_SPI" />
  </U2501>
</CircuitRoot>

My goal is check whether has some specify child.tag(ex:R7403、PR4426) under parents(ex: U7418、U2501) ,also check whether Power or Net in specify child.attrib is GND.

So, I want to extract each parent’s(U7418、U2501) child.tag and child.attirb

expect output is

{
U7418:{ R7402:[{PartNumber="64.20035" Net="LPS_SW_A"}], Q7406:[{PartNumber="075.00138" Pin="D2"}]... },
U2501:{ R2403:[{PartNumber="ZZ.R0402" Net="SHD_CS0#"}], PR4426:[{PartNumber="64.19635" Power="GND"}]...},
... 
}

but i think this expect output can be changed, since here might have better way to achieve my goal, the key point for me is how to paring this file.

I have tryed

import xml.etree.ElementTree as ET
tree = ET.parse(xml)
parent_map = {}
for p in tree.iter():
    for c in p:
        if c in parent_map:
            parent_map[c.tag].append(c.attrib)
        else:
            parent_map[c.tag] = [c.attrib]            
print(parent_map)

can get all child、subshild…tag and attrib, but i can get the corresponding parent.
[1]: https://i.stack.imgur.com/hpAmA.png

Thank you for your patience in reading to the end,
All help is greatly appreciated!