I am completely new to perl. I have had trouble understanding documentation; I think I don't understand all of the terminology. As such, I am not sure of the best way to phrase my questions. The examples here have been most helpful.

The code below works completely, but it feels like I am missing all of the perl and XML::Twig advantages. I feel like I should not need any foreach loops for this task.

1. How do I directly access the child with a specific gi and with a specific attribute of a specific value? I want to find the 'Instruction' element where 'Type'='Motor'. (There should only be one.)
2. How do I access the children where one of two attributes is a specific value? I want to find the FromID of wires that 'ToID'=$motorID OR the ToID of wires that 'FromID'=$motorID.
3. How do I access the child with ANY gi and with a specific attribute of a specific value? I want to access the 'Text' attribute of the child that 'ID'=$tofromID (discussed above in #2.)

Specifically, I want to link together a motor with all of its inputs and outputs. The output format is completely open. This is what I chose for its presenting ease with Excel.
Output:

<Motors>
  <Motor ID="2" Name="Motor2_name">
    <Motor_Input>Input_0_Text</Motor_Input>
    <Motor_Output>Output_1_Text</Motor_Output>
  </Motor>
  <Motor ID="2" Name="Motor_name">
    <Motor_Input>Input_0_Text</Motor_Input>
    <Motor_Output>Output_1_Text</Motor_Output>
  </Motor>
</Motors>
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Code:

use strict;
use warnings;
use XML::Twig;

my $XML='<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<Content>
  <Sheet>
    <Input ID="0" Text="Input_0_Text"/>
    <Output ID="1" Text="Output_1_Text"/>
    <Output ID="3" Text="Irrelevant_Output"/>
    <Instruction Type="Other"/>
    <Instruction Type="Motor" ID="2" Name="Motor_name"/>
    <Wire FromID="0" ToID="2" ToText="Motor_Input"/>
    <Wire FromID="2" ToID="1" FromText="Motor_Output"/>
  </Sheet>
  <Sheet>
    <Input ID="0" Text="Input_0_Text"/>
    <Output ID="1" Text="Output_1_Text"/>
    <Instruction Type="Motor" ID="2" Name="Motor2_name"/>
    <Wire FromID="0" ToID="2" ToText="Motor_Input"/>
    <Wire FromID="2" ToID="1" FromText="Motor_Output"/>
  </Sheet>  
</Content>';

# build a new file in the output format.
my $Output_file_name='testOutput.xml';
my $outRoot=XML::Twig::Elt->new('Motors');

#process input XML data
my $twig_roots={'Sheet'=>1};
my $twig_handlers={'Sheet' => \&Motors};
my $twig=new XML::Twig(TwigRoots=>$twig_roots, TwigHandlers=>$twig_han
+dlers);
$twig->parse($XML);

#output results
$outRoot->set_pretty_print('indented');
$outRoot->print_to_file($Output_file_name);

sub Motors{
  my ($twig, $Motor)=@_;
  my $motor_name="";
  my $motorID=-1;

#  I want to find the ID of the Motor Instruction
  
#  This seems like what I want to do  
#  $motorID = $Motor->first_child('Instruction')=>{Type=>'Motor'}->att
+('Name');
#  Error: "Can't call method "att" on unblessed reference..."

#  This works but seems to be non-twigish
  foreach my $instr ($Motor->children('Instruction')){ #iterate throug
+h all the instructions on this sheet
    if($instr->att('Type') eq 'Motor'){  #this instruction is a motor 
+type; set attributes
      $motorID=$instr->att('ID');
      $motor_name=$instr->att('Name');
      $outRoot->insert_new_elt('Motor'=>{Name=>$motor_name, ID=>$motor
+ID});
    }
  }

#  I want to find all wires that have a ToID or FromID that matches th
+e motorID  
  foreach my $wire ($Motor->children('Wire')){ #iterate through all wi
+res on this sheet

#    do once for ToID
    if($wire->att('ToID') == $motorID){  #this is a wire that goes to 
+the motor
      my $ToParam = $wire->att('ToText');
      my $FromID = $wire->att('FromID');
      my $FromText;
            
#nested foreach -> lots of iteration :(
      foreach my $motor_item ($Motor->children()){ #iterate though all
+ items on the sheet
        if (defined ($motor_item->att('ID'))){ #if the item has an ID 
+attribute
          if($motor_item->att('ID')==$FromID){ #that matches the wire 
+to the motor
            $FromText=$motor_item->att('Text'); #set output attribute
          }
        }
      }
      my $newRoot = $outRoot->first_child('Motor'=>{Name=>$motor_name}
+); #set current motor as root
      $newRoot->insert_new_elt('last_child', $ToParam, $FromText); #ad
+d this wire to output.
    }    
    
#    do again for FromID  pretty much the same as above.  
    if($wire->att('FromID') == $motorID){
      my $FromParam = $wire->att('FromText');
      my $ToID = $wire->att('ToID');
      my $ToText;

      foreach my $motor_item ($Motor->children()){
        if (defined ($motor_item->att('ID'))){
          if($motor_item->att('ID')==$ToID){
            $ToText=$motor_item->att('Text');
          }
        }
      }
      my $newRoot = $outRoot->first_child('Motor'=>{Name=>$motor_name}
+);
      $newRoot->insert_new_elt('last_child', $FromParam, $ToText);
    }    
  }
  
}
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