class_docstr: A simple keyring which just stores provided info in memory
  
  Primarily for testing
docstr: Delete password from the specified service.
          
docstr_tok: ["Delete","password","from","the","specified","service","."]
code: def delete(self, name, field=None):
      """Delete password from the specified service."""
      if name in self.entries:
          if field:
              self.entries[name].pop(field)
          else:
              # TODO: might be implemented by some super class if .keys() of some kind provided
              self.entries.pop(name)
      else:
          raise KeyError("No entries associated with %s" % name)
  
file_path: datalad/datalad/support/keyring_.py
imports: import os
  import logging
label_desc: Use image node_id 4 for calling the MemoryKeyring obj's underlying member method code with example usage: obj.delete(name, field) without return types