code: def fromfile(self, path_to_file, mimetype=None):
          
  
          if os.path.isfile(path_to_file):
  
              # Load file into self.__content__
              self.filename = os.path.basename(path_to_file)
              with open(path_to_file, "rb") as in_file:
                  self.content = in_file.read()
  
              #guess mime-type
              self.properties.content_settings = ContentSettings()
              
              if mimetype is None:
                  mimetype = guess_type(path_to_file)
                  if mimetype[0] is None:
                      mimetype = 'application/octet-stream'
                  else: 
                      if not mimetype[1] is None:
                          self.properties.content_settings.content_encoding = mimetype[1]
                      mimetype = mimetype[0]
  
              self.properties.content_settings.content_type = mimetype
  
          else:
              raise AzureStorageWrapException(self, 'Can not load blob content, because given path is not a local file')
docs: load blob content from file in StorageBlobModel instance. Parameters are:
          - path_to_file (required): path to a local file 
          - mimetype (optional): set a mimetype. azurestoragewrap will guess it if not given