(self, size=None)
return buf
Read at most size bytes from the file. If size is not
           present or None, read all data until EOF is reached.
Read at most size bytes from the file. If size is not
           present or None, read all data until EOF is reached.
Read at most size bytes from the file . If size is not present or None read all data until EOF is reached .
def read(self, size=None):
        """Read at most size bytes from the file. If size is not
           present or None, read all data until EOF is reached.
        """
        if self.closed:
            raise ValueError("I/O operation on closed file")

        buf = b""
        if self.buffer:
            if size is None:
                buf = self.buffer
                self.buffer = b""
            else:
                buf = self.buffer[:size]
                self.buffer = self.buffer[size:]

        if size is None:
            buf += self.fileobj.read()
        else:
            buf += self.fileobj.read(size - len(buf))

        self.position += len(buf)
        return buf
def read ( self , size = None ) : if self . closed : raise ValueError ( "I/O operation on closed file" ) buf = b"" if self . buffer : if size is None : buf = self . buffer self . buffer = b"" else : buf = self . buffer [ : size ] self . buffer = self . buffer [ size : ] if size is None : buf += self . fileobj . read ( ) else : buf += self . fileobj . read ( size - len ( buf ) ) self . position += len ( buf ) return buf