You can insert as many supplier attributes for a supplier as you want.
<SUPATTR_PROC_TYPE>
Mandatory.
Processing type.
Allowable values: I, U, and N.
'I' means that the object is to be inserted. ‘U’ means that an update is to be performed. ‘N’ means that the supplier attribute is not processed, that is, neither inserted nor modified. ‘N’ is not required for the supplier attributes, only for suppliers.
<SUPATTR_ATTR_CODE>
Mandatory.
Name (code) of the attribute.
<SUPATTR_ATTR_VALUE>
Mandatory.
Value of the attribute.