On sketching an equivalent circuit
The original schematic has an error in it, where D3 is called out twice:



Fixing that yields:



With +5V connected to GND through R3 and D3, D3 will be forward biased and there'll be about 0.7 volts across it, which puts the anode of D1 at about 0.7 volts, as well.

Then, with the 10 volt supply connected to R1 and D2, R1D1 will be reverse biased by about 9.3 volts and, since no charge will flow through them, they're effectively not in the circuit.

Re-annotating the schematic and explicitly showing the ground connection to the supplies yields this electrical simplification: