parameters: (cls, blob, marker)
docstring: Convert a binary blob to a PEM string.
  
          Args:
              blob: a single binary blob.
              marker: the marker to use in headers/footers.
  
          Returns:
              a string of concatenated PEM blobs.
docstring_summary: Convert a binary blob to a PEM string.
docstring_tokens: Convert a binary blob to a PEM string .
function: def pem_string(cls, blob, marker):
          """Convert a binary blob to a PEM string.
  
          Args:
              blob: a single binary blob.
              marker: the marker to use in headers/footers.
  
          Returns:
              a string of concatenated PEM blobs.
          """
          stringio = StringIO.StringIO()
          with cls(stringio, marker) as writer:
              writer.write(blob)
              return stringio.getvalue()
function_tokens: def pem_string ( cls , blob , marker ) : stringio = StringIO . StringIO ( ) with cls ( stringio , marker ) as writer : writer . write ( blob ) return stringio . getvalue ( )