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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def push(path, keep_symlinks=False, upload_path=None, remove_source=False):
    '''
    WARNING Files pushed to the master will have global read permissions..

    Push a file from the minion up to the master, the file will be saved to
    the salt master in the master's minion files cachedir
    (defaults to ``/var/cache/salt/master/minions/minion-id/files``)

    Since this feature allows a minion to push a file up to the master server
    it is disabled by default for security purposes. To enable, set
    ``file_recv`` to ``True`` in the master configuration file, and restart the
    master.

    keep_symlinks
        Keep the path value without resolving its canonical form

    upload_path
        Provide a different path inside the master's minion files cachedir

    remove_source
        Remove the source file on the minion

        .. versionadded:: 2016.3.0

    CLI Example:

    .. code-block:: bash

        salt '*' cp.push /etc/fstab
        salt '*' cp.push /etc/system-release keep_symlinks=True
        salt '*' cp.push /etc/fstab upload_path='/new/path/fstab'
        salt '*' cp.push /tmp/filename remove_source=True
    '''
    log.debug('Trying to copy \'%s\' to master', path)
    if '../' in path or not os.path.isabs(path):
        log.debug('Path must be absolute, returning False')
        return False
    if not keep_symlinks:
        path = os.path.realpath(path)
    if not os.path.isfile(path):
        log.debug('Path failed os.path.isfile check, returning False')
        return False
    auth = _auth()

    if upload_path:
        if '../' in upload_path:
            log.debug('Path must be absolute, returning False')
            log.debug('Bad path: %s', upload_path)
            return False
        load_path = upload_path.lstrip(os.sep)
    else:
        load_path = path.lstrip(os.sep)
    # Normalize the path. This does not eliminate
    # the possibility that relative entries will still be present
    load_path_normal = os.path.normpath(load_path)

    # If this is Windows and a drive letter is present, remove it
    load_path_split_drive = os.path.splitdrive(load_path_normal)[1]

    # Finally, split the remaining path into a list for delivery to the master
    load_path_list = [_f for _f in load_path_split_drive.split(os.sep) if _f]

    load = {'cmd': '_file_recv',
            'id': __opts__['id'],
            'path': load_path_list,
            'size': os.path.getsize(path),
            'tok': auth.gen_token(b'salt')}
    channel = salt.transport.client.ReqChannel.factory(__opts__)
    try:
        with salt.utils.files.fopen(path, 'rb') as fp_:
            init_send = False
            while True:
                load['loc'] = fp_.tell()
                load['data'] = fp_.read(__opts__['file_buffer_size'])
                if not load['data'] and init_send:
                    if remove_source:
                        try:
                            salt.utils.files.rm_rf(path)
                            log.debug('Removing source file \'%s\'', path)
                        except IOError:
                            log.error('cp.push failed to remove file \'%s\'', path)
                            return False
                    return True
                ret = channel.send(load)
                if not ret:
                    log.error('cp.push Failed transfer failed. Ensure master has '
                              '\'file_recv\' set to \'True\' and that the file '
                              'is not larger than the \'file_recv_size_max\' '
                              'setting on the master.')
                    return ret
                init_send = True
    finally:
        channel.close()