<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def get_headers_from_environ(environ):
 """Get a wsgiref.headers.Headers object with headers from the environment. Headers in environ are prefixed with 'HTTP_', are all uppercase, and have had dashes replaced with underscores. This strips the HTTP_ prefix and changes underscores back to dashes before adding them to the returned set of headers. Args: environ: An environ dict for the request as defined in PEP-333. Returns: A wsgiref.headers.Headers object that's been filled in with any HTTP headers found in environ. """

  headers = wsgiref.headers.Headers([])
  for header, value in environ.iteritems():
    if header.startswith('HTTP_'):
      headers[header[5:].replace('_', '-')] = value
  # Content-Type is special; it does not start with 'HTTP_'.
  if 'CONTENT_TYPE' in environ:
    headers['CONTENT-TYPE'] = environ['CONTENT_TYPE']
  return headers