Python lxml 没有可用于验证根的匹配全局声明

如何解决Python lxml 没有可用于验证根的匹配全局声明

我正在使用 lxml 解析器根据 XML 架构验证 xml 文档。xml 文档是：

<?xml version="1.0" encoding="UTF-8"?>
<KnittingModel modelname="mymodel"
        xmlns = "http://www.ludd21.com/KnittingModel">
        <Piece piecename="manche"> 
                <kPartList>kp1</kPartList>
                <kPartList>kp2</kPartList>
                <kPartList>kp3</kPartList>
        </Piece> 
        <Piece piecename="devant">
                <kPartList>kp4</kPartList>
                <kPartList>kp5</kPartList>
                <kPartList>kp6</kPartList>
                <kPartList>kp7</kPartList>
        </Piece>
</KnittingModel>

XMLSchema 是：

 <?xml version="1.0" encoding="UTF-8"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
targetNamespace = "http://www.ludd21.com/KnittingModel"
xmlns = "http://www.ludd21.com/KnittingModel"
  elementFormDefault="qualified">
  
<!--targetNameqpace specifies the namespace part of the name of all top-level elements -->
<!--attributes and types declared in the schema document -->
<!--xlmns attribute specifies how unprefixed names will be interpreted-->

  <!--<xs:import schemaLocation = "kPart.xsd"-->
  <!--namespace = "http://ludd21.com/KPartTypes" />-->
  
  <xsd:annotation>
    <xsd:documentation xml:lang="fr">
      Schéma XML pour un modèle de tricot
    </xsd:documentation>
  </xsd:annotation>
  
    
  <xsd:element name="knittingModel" >
    <xsd:complexType>
      <xsd:sequence>
      <xsd:element name = 'modelname' type = 'xsd:string'/>
       <xsd:element name="piece" minOccurs="1" maxOccurs="unbounded" type="Piece"/>
      </xsd:sequence>
    </xsd:complexType>
  </xsd:element>
  
    <xsd:simpleType name="KPart" >
      <xsd:restriction base = 'xsd:string'>
        <xsd:maxLength  value = "5" />
      </xsd:restriction>      
    </xsd:simpleType>
  
  
    <xsd:complexType name="KPartList">
      <xsd:sequence>    
        <xsd:element name="kPart" minOccurs="1" maxOccurs="unbounded" type = "KPart"/>
      </xsd:sequence>
    </xsd:complexType>
    
    <xsd:complexType name="Piece" >
       <xsd:sequence>
        <xsd:element name="piecename"  type="xsd:string" minOccurs="1" maxOccurs="unbounded"/>        
        <xsd:element name="kPartList" type = "KPartList"/>
       </xsd:sequence>
    </xsd:complexType>
  
</xsd:schema>

我收到以下错误：lxml.etree.XMLSyntaxError: Element '{http://www.ludd21.com/KnittingModel}KnittingModel': 没有匹配的全局声明可用于验证根。 (,第 0 行)

调用解析器的python指令是：

parser = ET.XMLParser(schema=xmlschema)
root = ET.fromstring(bytes(xmlknittingmodel,'utf-8'),parser)