parameters: (pem_file, markers)
docstring: Read a single PEM blob from a file.
  
      Ignores everything before and after the first blob with valid markers.
  
      Args:
          pem_file: the PEM file.
          markers: a single marker string or an iterable containing all
              accepted markers, such as CERTIFICATE, RSA PUBLIC KEY,
              PUBLIC KEY, etc.
  
      Returns:
          A (raw_string, marker) tuple containing the decoded blob and the
          marker used to detect the blob.
  
      Raises:
          PemError: a PEM block was invalid or no valid PEM block was found.
          IOError: the file could not be read.
docstring_summary: Read a single PEM blob from a file.
docstring_tokens: Read a single PEM blob from a file .
function: def from_pem_file(pem_file, markers):
      """Read a single PEM blob from a file.
  
      Ignores everything before and after the first blob with valid markers.
  
      Args:
          pem_file: the PEM file.
          markers: a single marker string or an iterable containing all
              accepted markers, such as CERTIFICATE, RSA PUBLIC KEY,
              PUBLIC KEY, etc.
  
      Returns:
          A (raw_string, marker) tuple containing the decoded blob and the
          marker used to detect the blob.
  
      Raises:
          PemError: a PEM block was invalid or no valid PEM block was found.
          IOError: the file could not be read.
      """
      with PemReader.from_file(pem_file, markers,
                               skip_invalid_blobs=False) as reader:
          return iter(reader).next()
function_tokens: def from_pem_file ( pem_file , markers ) : with PemReader . from_file ( pem_file , markers , skip_invalid_blobs = False ) as reader : return iter ( reader ) . next ( )