Input-Output format of UINT64 types

[ckeshava]

Inconsistency in str type input format:

UINT32 type accepts str type containing base-10 inputs, whereas UINT64 type accepts str type in base-16 format only. This is enforced by the differing HEX_REGEX and .isdigit() checks in their respective UInt<bits>.from_value() methods.

Furthermore, the documentation states that only UINT64 type is represented as a str, to ensure no loss of precision. This begs the question: why does UINT32 type accept str inputs?

Inconsistency in the .to_json() method output:

UINT32 type returns a value of type int represented in base-10 format.
UINT64 type returns a value of type str. This value is represented in base-16 format. While I understand the need for using a str type (for maintaining precision), why is base-16 the preferred output format?

Differences between xrpl.js and xrpl-py appropos handling UINT64 type

Juxtaposing xrpl-py's UInt64.from_value() method with this issue, the Javascript SDK accepts only hexa-decimal strings, whereas the Python SDK accepts both base-10 int's, and base-16 str inputs.

Examples of these inconsistencies can be observed in this branch