def _parse_value(self, html_data, field):
scheme = PLAYER_SCHEME[field]<EOL>items = [i.text() for i in html_data(scheme).items()]<EOL>if len(items) == <NUM_LIT:0>:<EOL><INDENT>return None<EOL><DEDENT>return items<EOL>
Parse the HTML table to find the requested field's value.

All of the values are passed in an HTML table row instead of as
individual items. The values need to be parsed by matching the
requested attribute with a parsing scheme that sports-reference uses
to differentiate stats. This function returns a single value for the
given attribute.

Parameters
----------
html_data : string
    A string containing all of the rows of stats for a given team. If
    multiple tables are being referenced, this will be comprised of
    multiple rows in a single string.
field : string
    The name of the attribute to match. Field must be a key in the
    PLAYER_SCHEME dictionary.

Returns
-------
list
    A list of all values that match the requested field. If no value
    could be found, returns None.